Tag Archives: astronomy

BigBang, Cosmology

Are FRBs Created by Aliens?

An FRB is an acronym coined by astronomers for fast radio burst. Since recent observations of our cosmos began with super-powerful telescopes only 17 such FRBs have ever been observed. These events last a mere handful of milliseconds but produce the equivalent power of around 100 million suns.

Two theories for these FRBs are relatively mundane. One theory proposes that FRBs are generated by powerful magnetars — highly magnetized, fast-rotating superdense stars. A second theory suggests that a FRB is a created by an especially exotic type of black hole.

And, then, there is a third, more fascinating, theory — that FRBs are the result of alien spaceship propulsion systems.

From the Economist:

Similar unrepeated signals have since been noted elsewhere in the heavens. So far, 17 such “fast radio bursts” (FRBs) have been recognised. They do not look like anything observed before, and there is much speculation about what causes them. One possibility is magnetars—highly magnetised, fast-rotating superdense stars. Another is a particularly exotic sort of black hole, formed when the centrifugal force of a rotating, superdense star proves no longer adequate to the task of stopping that star collapsing suddenly under its own gravity. But, as Manasvi Lingam of Harvard University and Abraham Loeb of the Harvard-Smithsonian Centre for Astrophysics observe, there is at least one further possibility: alien spaceships.

Specifically, the two researchers suggest, in a paper to be published in Astrophysical Journal Letters, that FRBs might be generated by giant radio transmitters designed to push such spaceships around. With the rotation of the galaxies in which these transmitters are located, the transmitter-beams sweep across the heavens. Occasionally, one washes over Earth, producing an FRB.

Read the entire article here.

Cosmology

Time to Move to Trappist-1

Those bright women and men at NASA have done it again. This time they’ve discovered 7 exoplanets all revolving around the same distant star. The cool news is that on the cosmological distance scale it’s relatively close, only around 40-light years away — a mere 230 trillion miles or so. And, even more fascinating, three of the system’s planets are within the so-called “Goldilocks” habitable zone.

The system is named TRAPPIST-1 (Transiting Planets and Planetesimals Small Telescope). The TRAPPIST telescope in Chile originally discovered 3  exoplanets. Now, using NASA’s Spitzer Space Telescope and the European Southern Observatory’s Very Large Telescope, researchers have upped the total to 7 exoplanets.

I’m ready. Now, just need a spacecraft, and a quick one at that.

From NASA:

NASA’s Spitzer Space Telescope has revealed the first known system of seven Earth-size planets around a single star. Three of these planets are firmly located in the habitable zone, the area around the parent star where a rocky planet is most likely to have liquid water.

The discovery sets a new record for greatest number of habitable-zone planets found around a single star outside our solar system. All of these seven planets could have liquid water – key to life as we know it – under the right atmospheric conditions, but the chances are highest with the three in the habitable zone.

“This discovery could be a significant piece in the puzzle of finding habitable environments, places that are conducive to life,” said Thomas Zurbuchen, associate administrator of the agency’s Science Mission Directorate in Washington. “Answering the question ‘are we alone’ is a top science priority and finding so many planets like these for the first time in the habitable zone is a remarkable step forward toward that goal.”

Read more here.

Image: An illustration of seven Earth-sized planets observed by NASA’s Spitzer Space Telescope around a tiny, nearby, ultra-cool dwarf star called TRAPPIST-1. Three of these planets are firmly in the habitable zone. Courtesy: NASA.

Cosmology

Vera Rubin: Astronomy Pioneer

Vera Rubin passed away on December 26, 2016, aged 88. She was a pioneer in the male-dominated world of astronomy, notable for her original work on dark matter,  galaxy rotation and galaxy clumping.

From Popular Science:

Vera Rubin, who essentially created a new field of astronomy by discovering dark matter, was a favorite to win the Nobel Prize in physics for years. But she never received her early-morning call from Stockholm. On Sunday, she died at the age of 88.

Rubin’s death would sadden the scientific community under the best of circumstances. Countless scientists were inspired by her work. Countless scientists are researching questions that wouldn’t exist if not for her work. But her passing brings another blow: The Nobel Prize cannot be awarded posthumously. The most prestigious award in physics will never be bestowed upon a woman who was inarguably deserving.

In the 1960s and ’70s, Rubin and her colleague Kent Ford found that the stars within spiral galaxies weren’t behaving as the laws of physics dictated that they should. This strange spinning led her and others to conclude that some unseen mass must be influencing the galactic rotation. This unknown matter—now dubbed dark matter—outnumbers the traditional stuff by at least five to one. This is a big deal.

Read more here.

Cosmology

Tabby’s Star

KIC_8462852_in_IR_and_UV

Tabby’s Star, officially known by the cryptic notation KIC 8462852 is a very odd object. The star is around 1,500 light years from Earth, and has been puzzling astronomers with its strangely fluctuating brightness. Recent analysis shows that is even weirder than first thought, which has scientists baffled. Could the observations be caused by a storm of wildly orbiting comets? Or, much more compelling (for SciFi buffs), could it be an alien megastructure periodically shrouding the star?

From Space:

KIC 8462852 was observed by NASA’s Kepler mission and has become infamous for its bizarre and unprecedented transit signal that was flagged by citizen scientists. Now new research of precision Kepler observations has shown that the overall brightness of the star — unofficially named “Tabby’s Star” after astronomer Tabetha S. Boyajian who discovered the peculiar signal — has been decreasing, which poses a new and confusing problem for astronomers trying to understand what the heck is going on.

Kepler’s prime mission is to look for small worlds that pass in front of their parent stars causing a slight dimming of starlight. The “transit method” has been hugely successful and has confirmed well over 2,000 planets orbiting other stars in our galaxy.

But Tabby’s Star’s transit signal, otherwise known as a “light-curve”, stopped astronomers in their tracks. Something passed in front of it, dimming its starlight a whopping 20 percent and other jumbled transit signals revealed that something wasn’t quite right with this particular star. Then, in an interview with The Atlantic, Penn State University astronomer Jason Wright speculated that the signal could be indicative of an “alien megastructure” that’s in the process of being built. You can catch up on the controversy surrounding the anomalous signal in my recent Discovery News article “Closing In on ‘Alien Megastructure’ Clues.”

…

So, in an effort to track down a rational explanation, Bradley Schaefer from Louisiana State University decided to study historical observations of KIC 8462852 in astronomical photographic plates from the past century to see if the star exhibited any bizarre fluctuations in brightness in the past. Sure enough, yes, the star is a bit of an oddball and has shown a long-term decreasing trend in brightness! Since the 19th Century, its brightness has decreased steadily by nearly 20 percent.

Now, astronomers Ben Montet (from Caltech) and Joshua Simon (from the Carnegie Institute) have released a paper to the arXiv preprint service detailing recent Kepler observations of KIC 8462852 since the space telescope was launched in 2009. Although the dataset for this time period is comparatively small, Monet and Simon found yet another surprise.

In the 4 years of Kepler’s primary mission, the star showed an unprecedented dimming of 3.5 percent. So not only did Kepler detect transient dips in brightness of up to 20 percent, there also seems to be a very definite downward trend in brightness throughout our observational history of the star.

No matter how you slice it, this is strange.

Read the entire story here.

Image: Tabby’s Star, KIC 8462852, in infrared (2MASS survey) and ultraviolet (GALEX). Courtesy: IPAC/NASA (Infrared), STScI/NASA (Ultraviolet). Public Domain.

Cosmology

Can We Move There?

Pale Red Dot is an international search for an Earth-like exoplanet around the closest star to us, Proxima Centauri. It will use HARPS, attached to ESO’s 3.6-metre telescope at La Silla Observatory, as well as the Las Cumbres Observatory Global Telescope Network (LCOGT) and the Burst Optical Observer and Transient Exploring System (BOOTES). It will be one of the few outreach campaigns allowing the general public to witness the scientific process of data acquisition in modern observatories. The public will see how teams of astronomers with different specialities work together to collect, analyse  and interpret data, which may or may not be able to confirm the presence of an Earth-like planet orbiting our nearest neighbour . The outreach campaign consists of blog posts and social media updates on the Pale Red Dot Twitter account and using the hashtag #PaleRedDot. For more information visit the Pale Red Dot website: http://www.palereddot.org

I’ve been toying with the idea of uprooting and moving to Canada should a certain orange-haired bigot win the US presidential election. But, no offense to Canadians, scientists have just discovered an Earth-like planet a mere 4.25 light-years away, our nearest celestial neighbor.

Can anyone convince Elon Musk (of SpaceX) to get cracking on a suitable spacecraft that will get us there, or at least help us leave, before November 8, 2016? Forget Mars, Proxima Centauri here I come!

From Space.com

The star closest to the sun hosts a planet that may be very much like Earth, a new study reports.

Astronomers have discovered a roughly Earth-size alien world around Proxima Centauri, which lies just 4.2 light-years from our own solar system. What’s even more exciting, study team members said, is that the planet, known as Proxima b, circles in the star’s “habitable zone” — the range of distances at which liquid water could be stable on a world’s surface.

“We hope these findings inspire future generations to keep looking beyond the stars,” lead author Guillem Anglada-Escude, a physics and astronomy lecturer at Queen Mary University of London, said in a statement.”The search for life on Proxima b comes next.” [In Pictures: The Discovery of Planet Proxima b]

A long search

The discovery of Proxima b was a long time in the making.

Astronomers have been hunting intensively for planets around Proxima Centauri for more 15 years, using instruments such as the Ultraviolet and Visual Echelle Spectrograph (UVES) and the High Accuracy Radial velocity Planet Searcher (HARPS), both of which are installed on telescopes run by the European Southern Observatory in Chile.

UVES, HARPS and other instruments like them allow researchers to detect the slight wobbles in a star’s movement caused by the gravitational tugs of orbiting planets.

Astronomers found hints of such a wobble back in 2013, but the signal was not convincing, Anglada-Escude said. So he and a number of other researchers launched a campaign to ferret out the planet. They called this effort the Pale Red Dot — a nod to Carl Sagan’s famous description of Earth as a “pale blue dot,” and the fact that Proxima Centauri is a small, dim star known as a red dwarf.

The Pale Red Dot team focused HARPS on Proxima Centauri every night from Jan. 19, 2016, through March 31 of this year. After they combined this new data with UVES observations from 2000 through 2008 and HARPS observations from 2005 through early 2014, the signal of a possible planet came through loud and clear.

Then, after analyzing observations of the star’s brightness made by several other telescopes, Anglada-Escude and his colleagues ruled out the possibility that this signal could be caused by the variable activity of Proxima Centauri.

“The conclusion: We have found a planet around Proxima Centauri,” Anglada-Escude said Tuesday (Aug. 23) during a news conference.

Read the entire story here.

Image: Pale Red Dot, an international search for an Earth-like exoplanet around the closest star to us, Proxima Centauri. It will use HARPS, attached to ESO’s 3.6-metre telescope at La Silla Observatory, as well as the Las Cumbres Observatory Global Telescope Network (LCOGT) and the Burst Optical Observer and Transient Exploring System (BOOTES). It will be one of the few outreach campaigns allowing the general public to witness the scientific process of data acquisition in modern observatories. The public will see how teams of astronomers with different specialities work together to collect, analyse and interpret data, which may or may not be able to confirm the presence of an Earth-like planet orbiting our nearest neighbour. The outreach campaign consists of blog posts and social media updates on the Pale Red Dot Twitter account and using the hashtag #PaleRedDot. For more information visit the Pale Red Dot website : http://www.palereddot.org. Courtesy: ESO/Pale Red Dot – http://www.eso.org/public/images/ann16002a/

Cosmology

The Case For Planet Nine

Planet_nine_artistic-impression

First, let me say that Pluto should never have been downgraded to the status of “dwarf planet”. The recent (and ongoing) discoveries by NASA’s New Horizons probe show Pluto’s full, planetary glory: kilometer high mountains, flowing glaciers, atmospheric haze, organic compounds, complex and colorful landforms. So, in my mind Pluto still remains as the ninth planet in our beautiful solar system.

However, many astronomers have moved on and are getting excited over the possibility of a new Planet Nine. The evidence for its existence is mounting and comes mostly from models that infer the presence of a massive object far-beyond Pluto, which is influencing the orbits of asteroids and even some of the outer planets.

From Scientific American:

The hunt is on to find “Planet Nine”—a large undiscovered world, perhaps 10 times as massive as Earth and four times its size—that scientists think could be lurking in the outer solar system. After Konstantin Batygin and Mike Brown, two planetary scientists from the California Institute of Technology, presented evidence for its existence this January, other teams have searched for further proof by analyzing archived images and proposing new observations to find it with the world’s largest telescopes.

Just this month, evidence from the Cassini spacecraft orbiting Saturn helped close in on the missing planet. Many experts suspect that within as little as a year someone will spot the unseen world, which would be a monumental discovery that changes the way we view our solar system and our place in the cosmos. “Evidence is mounting that something unusual is out there—there’s a story that’s hard to explain with just the standard picture,” says David Gerdes, a cosmologist at the University of Michigan who never expected to find himself working on Planet Nine. He is just one of many scientists who leapt at the chance to prove—or disprove—the team’s careful calculations.

Batygin and Brown made the case for Planet Nine’s existence based on its gravitational effect on several Kuiper Belt objects—icy bodies that circle the sun beyond Neptune’s orbit. Theoretically, though, its gravity should also tug slightly on the planets.* With this in mind, Agnès Fienga at the Côte d’Azur Observatory in France and her colleagues checked whether a theoretical model (one that they have been perfecting for over a decade) with the new addition of Planet Nine could better explain slight perturbations seen in Saturn’s orbit as observed by Cassini.* Without it, the other seven planets in the solar system, 200 asteroids and five of the most massive Kuiper Belt objects cannot perfectly account for it.* The missing puzzle piece might just be a ninth planet.

So Fienga and her colleagues compared the updated model, which placed Planet Nine at various points in its hypothetical orbit, with the data. They found a sweet spot—with Planet Nine 600 astronomical units (about 90 billion kilometers) away toward the constellation Cetus—that can explain Saturn’s orbit quite well.* Although Fienga is not yet convinced that she has found the culprit for the planet’s odd movements, most outside experts are blown away.* “It’s a brilliant analysis,” says Greg Laughlin, an astronomer at Lick Observatory, who was not involved in the study. “It’s completely amazing that they were able to do that so quickly.” Gerdes agrees: “That’s a beautiful paper.”

The good news does not end there. If Planet Nine is located toward the constellation Cetus, then it could be picked up by the Dark Energy Survey, a Southern Hemisphere observation project designed to probe the acceleration of the universe. “It turns out fortuitously that the favored region from Cassini’s data is smack dab in the middle of our survey footprint,” says Gerdes, who is working on the cosmology survey.* “We could not have designed our survey any better.” Although the survey was not planned to search for solar system objects, Gerdes has discovered some (including one of the icy objects that led Batygin and Brown to conclude Planet Nine exists in the first place).

Read the entire article here.

Image: Artist’s impression of Planet Nine as an ice giant eclipsing the central Milky Way, with a star-like Sun in the distance. Neptune’s orbit is shown as a small ellipse around the Sun. Courtesy: Tomruen, nagualdesign / Wikipedia. Creative Commons.

BigBang, Cosmology

Another Glorious Hubble Image

This NASA/ESA Hubble Space Telescope image shows the spiral galaxy NGC 4845, located over 65 million light-years away in the constellation of Virgo (The Virgin). The galaxy’s orientation clearly reveals the galaxy’s striking spiral structure: a flat and dust-mottled disc surrounding a bright galactic bulge. NGC 4845’s glowing centre hosts a gigantic version of a black hole, known as a supermassive black hole. The presence of a black hole in a distant galaxy like NGC 4845 can be inferred from its effect on the galaxy’s innermost stars; these stars experience a strong gravitational pull from the black hole and whizz around the galaxy’s centre much faster than otherwise. From investigating the motion of these central stars, astronomers can estimate the mass of the central black hole — for NGC 4845 this is estimated to be hundreds of thousands times heavier than the Sun. This same technique was also used to discover the supermassive black hole at the centre of our own Milky Way — Sagittarius A* — which hits some four million times the mass of the Sun (potw1340a). The galactic core of NGC 4845 is not just supermassive, but also super-hungry. In 2013 researchers were observing another galaxy when they noticed a violent flare at the centre of NGC 4845. The flare came from the central black hole tearing up and feeding off an object many times more massive than Jupiter. A brown dwarf or a large planet simply strayed too close and was devoured by the hungry core of NGC 4845.

The Hubble Space Telescope captured this recent image of spiral galaxy NGC 4845. The galaxy lies around 65 million light-years from Earth, but it still presents a gorgeous sight. NGC 4845’s glowing center hosts a supermassive, and super hungry, black hole.

Thanks NASA, but I just wish you would give these galaxies more memorable names.

Image: NASA/ESA Hubble Space Telescope image shows the spiral galaxy NGC 4845, located over 65 million light-years away in the constellation of Virgo. Courtesy: ESA/Hubble & NASA and S. Smartt (Queen’s University Belfast).

BigBang, Cosmology

A Gravitational Wave Comes Ashore

ligo-gravitational-waves-detection

On February 11, 2016, a historic day for astronomers the world over, scientists announced a monumental discovery, which was made on September 14, 2015! Thank you LIGO, the era of gravitational wave (G-Wave) astronomy has begun.

One hundred years after a prediction from Einstein’s theory of general relativity scientists have their first direct evidence of gravitational waves. These waves are ripples in the fabric of spacetime itself rather than the movement of fields and particles, such as from electromagnetic radiation. These ripples show up when gravitationally immense bodies warp the structure of space in which they sit, such as through collisions or acceleration.

ligo-hanford-aerial

As you might imagine for such disturbances to be observed here on Earth over distances in the tens to hundreds of millions, of light-years requires not only vastly powerful forces at one end but immensely sensitive instruments at the other. In fact the detector credited with discovery in this case is the Laser Interferometer Gravitational-Wave Observatory, or LIGO. It is so sensitive it can detect a change in length of its measurement apparatus — infra-red laser beams — 10,000 times smaller than the width of a proton. LIGO is operated by Caltech and MIT and supported through the U.S. National Science Foundation.

Prof Kip Thorne, one of the founders of LIGO, said that until now, astronomers had looked at the universe as if on a calm sea. This is now changed. He adds:

“The colliding black holes that produced these gravitational waves created a violent storm in the fabric of space and time, a storm in which time speeded up and slowed down, and speeded up again, a storm in which the shape of space was bent in this way and that way.”

And, as Prof Stephen Hawking remarked:

“Gravitational waves provide a completely new way of looking at the universe. The ability to detect them has the potential to revolutionise astronomy. This discovery is the first detection of a black hole binary system and the first observation of black holes merging.”

Congratulations to the many hundreds of engineers, technicians, researchers and theoreticians who have collaborated on this ground-breaking experiment. Particular congratulations go to LIGO’s three principal instigators: Rainier Weiss, Kip Thorne, and Ronald Drever.

This discovery paves the way for deeper understanding of our cosmos and lays the foundation for a new and rich form of astronomy through gravitational observations.

Galileo’s first telescopes opened our eyes to the visual splendor of our solar system and its immediate neighborhood. More recently, radio-wave, x-ray and gamma-ray astronomy have allowed us to discover wonders further afield: star-forming nebulae, neutron stars, black holes, active galactic nuclei, the Cosmic Microwave Background (CMB). Now, through LIGO and its increasingly sensitive descendants we are likely to make even more breathtaking discoveries, some of which, courtesy of gravitational waves, may let us peer at the very origin of the universe itself — the Big Bang.

How brilliant is that!

Image 1: The historic detection of gravitational waves by the Laser Interferometer Gravitational-Wave Observatory (LIGO) is shown in this plot during a press conference in Washington, D.C. on Feb. 11, 2016.Courtesy: National Science Foundation.

Image 2: LIGO Laboratory operates two detector sites 1,800 miles apart: one near Hanford in eastern Washington, and another near Livingston, Louisiana. This photo shows the Hanford detector. Courtesy of LIGO Caltech.

 

BigBang

Titan Close Up

You could be forgiven for thinking the image below is of Earth. Rather, it is Saturn’s largest moon, Titan, as imaged in infra-red by NASA’s Cassini spacecraft on November 13, 2015. Gorgeous.

Titan-Cassini- flyby-13Nov2015

Image: Composite image shows an infrared view of Saturn’s moon Titan from NASA’s Cassini spacecraft, acquired during the mission’s “T-114” flyby on Nov. 13, 2015. Courtesy NASA.

BigBang

The Curious Case of the Strange Transit Signal

Something very strange is happening over at KIC 8462852. But, it may not be an alien intelligence.

KIC-8462852–Where-is-the-flux

NASA’s extrasolar, planet-hunting space telescope, found some odd changes in the luminosity of a star — KIC 8462852— located in the constellation of Cygnus, about 1,400 light-years from Earth. In a recent paper submitted to the Royal Astronomical Society, astronomers reported that:

“Over the duration of the Kepler mission, KIC 8462852 was observed to undergo irregularly shaped, aperiodic dips in flux down to below the 20 percent level.”

But despite several years of monitoring, astronomers have yet to come up with a feasible, natural explanation. And, this has conspiracy theorists, alien hunters and SciFi enthusiasts very excited. Could it be a massive alien structure shielding the star, or is there simpler and natural, but less amazing possibility? Occam’s razor could well prevail again, but I certainly hope not in this case.

From Wired:

Last week, astronomers—amateur and pro—got excited about some strange results from the Kepler Space Telescope, the NASA observatory tasked with searching for Earth-like planets. As those planets orbit their own distant suns, periodically blocking light from Kepler’s view, the telescope documents the flickers. But over the last several years, it has picked up a strange pattern of blips from one star in particular, KIC 8462852.

Light from that star dramatically plunges in irregular intervals—not the consistent pattern you’d expect from an orbiting planet. But what could possibly cause such a thing? Gotta be aliens, right? Clearly someone—something—has assembled a megastructure around its sun, like that hollow Celestial head in Guardians of the Galaxy. Or maybe it’s a solar array, collecting energy-giving radiation and preventing light from reaching NASA’s telescope.

This, of course, is almost certainly poppycock. When you’re searching the vast expanse of space, lots of things look like they could be signs of extraterrestrial life. Astronomical observers are constantly looking for tiny glimmers of information in the mess of noise that streams through space toward Earth, and often, things that at first look like signals end up being mirages. This has all happened before; it will all happen again. For example:

Pulsars

In 1967, astronomer Jocelyn Bell was monitoring signals from the Mullard Radio Astronomy Observatory, trying to analyze the behavior of quasars, energy-spewing regions surrounding supermassive black holes within distant galaxies. What she found, though, was a series of regular pulses, always from the same part of the sky, that she labeled LGM-1: Little Green Men. Soon, though, she found similar signals coming from another part of the sky, and realized that she wasn’t seeing messages from two different alien civilizations: It was radiation from a spinning, magnetized neutron star—the first measured pulsar.

…

Sparks at Parkes

In 1998, astronomers at the 64-meter Parkes radio telescope in Australia started noticing mysterious radio signals called perytons—unexplained, millisecond-long bursts. The researchers there didn’t immediately cry alien, though; they could tell that the radio signals were terrestrial in origin, because they showed up across the entire spectrum monitored by the telescope. They didn’t know until this year, however, exactly where those emissions came from: a microwave oven on the observatory’s campus, which released a short, powerful radio signal when staffers opened its door in the middle of heating.

Read the entire story here.

Image: Flux time series for KIC 8462852 showing different portions of the 4-year Kepler observations. Courtesy: T. S. Boyajian et al, Planet Hunters X. KIC 8462852 – Where’s the flux?

 

 

BigBang, Environs

MondayMap: Our Beautiful Blue Home

OK, OK, I cheated a little this week. I don’t have a map story.

But I couldn’t resist posting the geographic-related news of NASA’s new website. Each day, the agency will post a handful of images of our gorgeous home, as seen from the DSCOVR spacecraft. DSCOVR is parked at the L-1 Lagrangian Point, about 1 million miles from Earth and 92 million from the Sun, where the gravitational forces of the three bodies balance. It’s a wonderful vantage point to peer at our beautiful blue planet.

DSCOVR-Earth-image-19Oct2015

You can check out NASA’s new website here.

Image: Earth as imaged from DSCOVR on October 19, 2015. Courtesy of NASA, NOAA and the U.S Air Force.

BigBang

The Big Breakthrough Listen

If you were a Russian billionaire with money to burn and a penchant for astronomy and physics what would you do? Well, rather than spend it on a 1,000 ft long super-yacht, you might want to spend it on the search for extraterrestrial intelligence. That’s what Yuri Milner is doing. So, hats off to him and his colleagues.

Though, I do hope any far-distant aliens have similar, or greater, sums of cash to throw at equipment to transmit a signal so that we may receive it. Also, I have to wonder what alien oligarchs spend their excess millions and billions on — and what type of monetary system they use (hopefully not Euros).

From the Guardian:

Astronomers are to embark on the most intensive search for alien life yet by listening out for potential radio signals coming from advanced civilisations far beyond the solar system.

Leading researchers have secured time on two of the world’s most powerful telescopes in the US and Australia to scan the Milky Way and neighbouring galaxies for radio emissions that betray the existence of life elsewhere. The search will be 50 times more sensitive, and cover 10 times more sky, than previous hunts for alien life.

The Green Bank Observatory in West Virginia, the largest steerable telescope on the planet, and the Parkes Observatory in New South Wales, are contracted to lead the unprecedented search that will start in January 2016. In tandem, the Lick Observatory in California will perform the most comprehensive search for optical laser transmissions beamed from other planets.

Operators have signed agreements that hand the scientists thousands of hours of telescope time per year to eavesdrop on planets that orbit the million stars closest to Earth and the 100 nearest galaxies. The telescopes will scan the centre of the Milky Way and the entire length of the galactic plane.

Launched on Monday at the Royal Society in London, with the Cambridge cosmologist Stephen Hawking, the Breakthrough Listen project has some of the world’s leading experts at the helm. Among them are Lord Martin Rees, the astronomer royal, Geoff Marcy, who has discovered more planets beyond the solar system than anyone, and the veteran US astronomer Frank Drake, a pioneer in the search for extraterrestrial intelligence (Seti).

Stephen Hawking said the effort was “critically important” and raised hopes for answering the question of whether humanity has company in the universe. “It’s time to commit to finding the answer, to search for life beyond Earth,” he said. “Mankind has a deep need to explore, to learn, to know. We also happen to be sociable creatures. It is important for us to know if we are alone in the dark.”

The project will not broadcast signals into space, because scientists on the project believe humans have more to gain from simply listening out for others. Hawking, however, warned against shouting into the cosmos, because some advanced alien civilisations might possess the same violent, aggressive and genocidal traits found among humans.

“A civilisation reading one of our messages could be billions of years ahead of us. If so they will be vastly more powerful and may not see us as any more valuable than we see bacteria,” he said.

The alien hunters are the latest scientists to benefit from the hefty bank balance of Yuri Milner, a Russian internet billionaire, who quit a PhD in physics to make his fortune. In the past five years, Milner has handed out prizes worth tens of millions of dollars to physicists, biologists and mathematicians, to raise the public profile of scientists. He is the sole funder of the $100m Breakthrough Listen project.

“It is our responsibility as human beings to use the best equipment we have to try to answer one of the biggest questions: are we alone?” Milner told the Guardian. “We cannot afford not to do this.”

Milner was named after Yuri Gagarin, who became the first person to fly in space in 1961, the year he was born.

The Green Bank and Parkes observatories are sensitive enough to pick up radio signals as strong as common aircraft radar from planets around the nearest 1,000 stars. Civilisations as far away as the centre of the Milky Way could be detected if they emit radio signals more than 10 times the power of the Arecibo planetary radar on Earth. The Lick Observatory can pick up laser signals as weak as 100W from nearby stars 25tn miles away.

Read the entire story here.

BigBang

Europa Here We Come

NASA-Europa

With the the European Space Agency’s (ESA) Philae lander firmly rooted to a comet, NASA’s Dawn probe orbiting dwarf planet Ceres and its New Horizon’s spacecraft hurtling towards Pluto and Charon it would seem that we are doing lots of extraterrestrial exploration lately. Well, this is exciting, but for arm-chair explorers like myself this is still not enough. So, three cheers to NASA for giving a recent thumbs up to their next great mission — Europa Multi Flyby — to Jupiter’s moon, Europa.

Development is a go! But we’ll have to wait until the mid-2020s for lift-off. And, better yet, ESA has a mission to Europa planned for launch in 2022. Can’t wait — it looks spectacular.

From ars technica:

Get ready, we’re going to Europa! NASA’s plan to send a spacecraft to explore Jupiter’s moon just passed a major hurdle. The mission, planned for the 2020s, now has NASA’s official stamp of approval and was given the green light to move from concept phase to development phase.

Formerly known as Europa Clipper, the mission will temporarily be referred to as the Europa Multi Flyby Mission until it is given an official name. The current mission plan would include 45 separate flybys around the moon while orbiting Jupiter every two weeks. “We are taking an exciting step from concept to mission in our quest to find signs of life beyond Earth,” John Grunsfeld, associate administrator for NASA’s Science Mission Directorate, said in a press release.

Since Galileo first turned a spyglass up to the skies and discovered the Jovian moon, Europa has been a world of intrigue. In the 1970s, we received our first look at Europa through the eyes of Pioneer 10 and 11, followed closely by the twin Voyager satellites in the 1980s. Their images provided the first detailed view of the Solar System’s smoothest body. These photos also delivered evidence that the moon might be harboring a subsurface ocean. In the mid 1990s, the Galileo spacecraft gave us the best view to-date of Europa’s surface.

“Observations of Europa have provided us with tantalizing clues over the last two decades, and the time has come to seek answers to one of humanity’s most profound questions,” Grunsfeld said. “Mainly, is there life beyond Earth?”

Sending a probe to explore Jupiter’s icy companion will help scientists in the search for this life. If Europa can support microbial life, other glacial moons such as Enceladus might as well.

Water, chemistry, and energy are three components essential to the presence of life. Liquid water is present throughout the Solar System, but so far the only world known to support life is Earth. Scientists think that if we follow the water, we may find evidence of life beyond Earth.

However, water alone will not support life; the right combination of ingredients is key. This mission to Europa will explore the moon’s potential habitability as opposed to outright looking for life.

When we set out to explore new worlds, we do it in phases. First we flyby, then we send robotic landers, and then we send people. This three-step process is how we, as humans, have explored the Moon and how we are partly through the process of exploring Mars.

The flyby of Europa will be a preliminary mission with four objectives: explore the ice shell and subsurface ocean; determine the composition, distribution, and chemistry of various compounds and how they relate to the ocean composition; map surface features and determine if there is current geologic activity; characterize sites to determine where a future lander might safely touch down.

Europa, at 3,100 kilometers wide (1,900 miles), is the sixth largest moon in the Solar System. It has a 15 to 30 kilometer (9 to 18 mile) thick icy outer crust that covers a salty subsurface ocean. If that ocean is in contact with Europa’s rocky mantle, a number of complex chemical reactions are possible. Scientists think that hydrothermal vents lurk on the seafloor, and, just like the vents here on Earth, they could support life.

The Galileo orbiter taught us most of what we know about Europa through 12 flybys of the icy moon. The new mission is scheduled to conduct approximately 45 flybys over a 2.5-year period, providing even more insight into the moon’s habitability.

Read the article here.

Image: Europa. Europa is Jupiter’s sixth-closest moon, and the sixth-largest moon in the Solar System. Courtesy of NASA.

BigBang

Earth 2.0: Kepler 452b

452b_artistconcept_beautyshot

On July 23, 2015 NASA announced discovery of Kepler 452b, an Earth-like exoplanet, which they dubbed Earth 2.0. Found following a four-year trawl through data from the Kepler exoplanet-hunting space telescope, Kepler 452b is the closest exoplanet yet in its resemblance to Earth. It revolves around its sun-like home star in 380 days at a distance similar to that between Earth and our sun (93 million miles).

Unfortunately, Kepler 452b is a “mere” 1,400 light years away — so you can forget trying to strike up a real-time conversation with any of its intelligent inhabitants. If it does harbor life I have to hope that any sentient lifeforms have taken better care of their home than we earthlings do of our own. Then again, it may be better that the exoplanet hosts only non-intelligent life!

Here’s NASA’s technical paper.

Check out NASA’s briefing here.

Image: Artist rendition of Kepler 452b. Courtesy of NASA. Public Domain.

BigBang

Hello Pluto

Pluto-New-Horizons-14Jul2015

Today NASA’s New Horizons spacecraft reached the (dwarf) planet Pluto and its five moons. After a 9.5 year voyage covering around 3 billion miles, the refrigerator-sized probe has finally reached its icy target. Unfortunately, New Horizons is traveling so quickly it will not enter orbit around Pluto but continue its 30,000 mph trek into interstellar space. The images, and science, that the craft will stream back to Earth over the coming months should be spectacular.

Check out more on the New Horizon’s mission here.

Image: Pluto as imaged by New Horizons, last image prior to its closest approach on July 14, 2015. Images courtesy of NASA.

BigBang

Active SETI

google-search-aliens

Seventy years after the SETI (Search for Extra-Terrestrial Intelligence) experiment began some astronomers are thinking of SETI 2.0 or active SETI. Rather than just passively listening for alien-made signals emanating from the far distant exoplanets these astronomers wish to take the work a bold step further. They’re planning to transmit messages in the hope that someone or something will be listening. And that has opponents of the plan rather worried. If somethings do hear us, will they come looking, and if so, then what? Will the process result in a real-life The Day the Earth Stood Still or Alien? And, more importantly, will they all look astonishingly Hollywood-like?

From BBC:

Scientists at a US conference have said it is time to try actively to contact intelligent life on other worlds.

Researchers involved in the search for extra-terrestrial life are considering what the message from Earth should be.

The call was made by the Search for Extra Terrestrial Intelligence institute at a meeting of the American Association for the Advancement of Science in San Jose.

But others argued that making our presence known might be dangerous.

Researchers at the Seti institute have been listening for signals from outer space for more than 30 years using radio telescope facilities in the US. So far there has been no sign of ET.

The organisation’s director, Dr Seth Shostak, told attendees to the AAAS meeting that it was now time to step up the search.

“Some of us at the institute are interested in ‘active Seti’, not just listening but broadcasting something to some nearby stars because maybe there is some chance that if you wake somebody up you’ll get a response,” he told BBC News.

The concerns are obvious, but sitting in his office at the institute in Mountain View, California, in the heart of Silicon Valley, he expresses them with characteristic, impish glee.

Game over?

“A lot of people are against active Seti because it is dangerous. It is like shouting in the jungle. You don’t know what is out there; you better not do it. If you incite the aliens to obliterate the planet, you wouldn’t want that on your tombstone, right?”

I couldn’t argue with that. But initially, I could scarcely believe I was having this conversation at a serious research institute rather than at a science fiction convention. The sci-fi feel of our talk was underlined by the toy figures of bug-eyed aliens that cheerfully decorate the office.

But Dr Shostak is a credible and popular figure and has been invited to present his arguments.

Leading astronomers, anthropologists and social scientists will gather at his institute after the AAAS meeting for a symposium to flesh out plans for a proposal for active Seti to put to the public and politicians.

High on the agenda is whether such a move would, as he put it so starkly, lead to the “obliteration” of the planet.

“I don’t see why the aliens would have any incentive to do that,” Dr Shostak tells me.

“Beyond that, we have been telling them willy-nilly that we are here for 70 years now. They are not very interesting messages but the early TV broadcasts, the early radio, the radar from the Second World War – all that has leaked off the Earth.

“Any society that could come here and ruin our whole day by incinerating the planet already knows we are here.”

Read the entire article here.

Image courtesy of Google Search.

BigBang

MondayMap: Our New Address — Laniakea

laniakea_nrao

Once upon a time we humans sat smugly at the center of the universe. Now, many of us (though, not yet all) know better. Over the the last several centuries we learned and accepted that the Earth spun around the nearest Star, and not the converse. We then learned that the Sun formed part of an immense galaxy, the Milky Way, itself spinning in a vast cosmological dance. More recently, we learned that the Milky Way formed part of a larger cluster of galaxies, known as the Local Group.

Now we find that our Local Group is a mere speck within an immense supercluster containing around 100,000 galaxies spanning half a billion light years. Researchers have dubbed this galactic supercluster, rather aptly, Laniakea, Hawaiian for “immense heaven”. Laniakea is your new address. And, fascinatingly, Laniakea is moving towards an even larger grouping of galaxies named the Shapely supercluster.

From the Guardian:

In what amounts to a back-to-school gift for pupils with nerdier leanings, researchers have added a fresh line to the cosmic address of humanity. No longer will a standard home address followed by “the Earth, the solar system, the Milky Way, the universe” suffice for aficionados of the extended astronomical location system.

The extra line places the Milky Way in a vast network of neighbouring galaxies or “supercluster” that forms a spectacular web of stars and planets stretching across 520m light years of our local patch of universe. Named Laniakea, meaning “immeasurable heaven” in Hawaiian, the supercluster contains 100,000 large galaxies that together have the mass of 100 million billion suns.

Our home galaxy, the Milky Way, lies on the far outskirts of Laniakea near the border with another supercluster of galaxies named Perseus-Pisces. “When you look at it in three dimensions, is looks like a sphere that’s been badly beaten up and we are over near the edge, being pulled towards the centre,” said Brent Tully, an astronomer at the University of Hawaii in Honolulu.

Astronomers have long known that just as the solar system is part of the Milky Way, so the Milky Way belongs to a cosmic structure that is much larger still. But their attempts to define the larger structure had been thwarted because it was impossible to work out where one cluster of galaxies ended and another began.

Tully’s team gathered measurements on the positions and movement of more than 8,000 galaxies and, after discounting the expansion of the universe, worked out which were being pulled towards us and which were being pulled away. This allowed the scientists to define superclusters of galaxies that all moved in the same direction (if you’re reading this story on a mobile device, click here to watch a video explaining the research).

The work published in Nature gives astronomers their first look at the vast group of galaxies to which the Milky Way belongs. A narrow arch of galaxies connects Laniakea to the neighbouring Perseus-Pisces supercluster, while two other superclusters called Shapley and Coma lie on the far side of our own.

Tully said the research will help scientists understand why the Milky Way is hurtling through space at 600km a second towards the constellation of Centaurus. Part of the reason is the gravitational pull of other galaxies in our supercluster.

“But our whole supercluster is being pulled in the direction of this other supercluster, Shapley, though it remains to be seen if that’s all that’s going on,” said Tully.

Read the entire article here or the nerdier paper here.

Image: Laniakea: Our Home Supercluster of Galaxies. The blue dot represents the location of the Milky Way. Courtesy: R. Brent Tully (U. Hawaii) et al., SDvision, DP, CEA/Saclay.

BigBang

European Extremely Large Telescope

Rendering_of_the_E-ELT

When it is cited in the high mountains in the Chilean coastal desert the European Extremely Large Telescope (or E-ELT) will be the biggest and the baddest telescope to date.  With a mirror having a diameter of around 125 feet, the E-ELT will give observers unprecedented access to the vast panoramas of the cosmos. Astronomers are even confident that when it is fully operational, in about 2030, the telescope will be able to observe exo-planets directly, for the first time.

From the Observer:

Cerro Armazones is a crumbling dome of rock that dominates the parched peaks of the Chilean Coast Range north of Santiago. A couple of old concrete platforms and some rusty pipes, parts of the mountain’s old weather station, are the only hints that humans have ever taken an interest in this forbidding, arid place. Even the views look alien, with the surrounding boulder-strewn desert bearing a remarkable resemblance to the landscape of Mars.

Dramatic change is coming to Cerro Armazones, however – for in a few weeks, the 10,000ft mountain is going to have its top knocked off. “We are going to blast it with dynamite and then carry off the rubble,” says engineer Gird Hudepohl. “We will take about 80ft off the top of the mountain to create a plateau – and when we have done that, we will build the world’s biggest telescope there.”

Given the peak’s remote, inhospitable location that might sound an improbable claim – except for the fact that Hudepohl has done this sort of thing before. He is one of the European Southern Observatory’s most experienced engineers and was involved in the decapitation of another nearby mountain, Cerro Paranal, on which his team then erected one of the planet’s most sophisticated observatories.

The Paranal complex has been in operation for more than a decade and includes four giant instruments with eight-metre-wide mirrors – known as the Very Large Telescopes or VLTs – as well as control rooms and a labyrinth of underground tunnels linking its instruments. More than 100 astronomers, engineers and support staff work and live there. A few dozen metres below the telescopes, they have a sports complex with a squash court, an indoor football pitch, and a luxurious 110-room residence that has a central swimming pool and a restaurant serving meals and drinks around the clock. Built overlooking one of the world’s driest deserts, the place is an amazing oasis. (See box.)

Now the European Southern Observatory, of which Britain is a key member state, wants Hudepohl and his team to repeat this remarkable trick and take the top off Cerro Armazones, which is 20km distant. Though this time they will construct an instrument so huge it will dwarf all the telescopes on Paranal put together, and any other telescope on the planet. When completed, the European Extremely Large Telescope (E-ELT) and its 39-metre mirror will allow astronomers to peer further into space and look further back into the history of the universe than any other astronomical device in existence. Its construction will push telescope-making to its limit, however. Its primary mirror will be made of almost 800 segments – each 1.4 metres in diameter but only a few centimetres thick – which will have to be aligned with microscopic precision.

It is a remarkable juxtaposition: in the midst of utter desolation, scientists have built giant machines engineered to operate with smooth perfection and are now planning to top this achievement by building an even more vast device. The question is: for what purpose? Why go to a remote wilderness in northern Chile and chop down peaks to make homes for some of the planet’s most complex scientific hardware?

The answer is straightforward, says Cambridge University astronomer Professor Gerry Gilmore. It is all about water. “The atmosphere here is as dry as you can get and that is critically important. Water molecules obscure the view from telescopes on the ground. It is like trying to peer through mist – for mist is essentially a suspension of water molecules in the air, after all, and they obscure your vision. For a telescope based at sea level that is a major drawback.

“However, if you build your telescope where the atmosphere above you is completely dry, you will get the best possible views of the stars – and there is nowhere on Earth that has air drier than this place. For good measure, the high-altitude winds blow in a smooth, laminar manner above Paranal – like slabs of glass – so images of stars remain remarkably steady as well.”

The view of the heavens here is close to perfect, in other words – as an evening stroll around the viewing platform on Paranal demonstrates vividly. During my visit, the Milky Way hung over the observatory like a single white sheet. I could see the four main stars of the Southern Cross; Alpha Centauri, whose unseen companion Proxima Centauri is the closest star to our solar system; the two Magellanic Clouds, satellite galaxies of our own Milky Way; and the Coalsack, an interstellar dust cloud that forms a striking silhouette against the starry Milky Way. None are visible in northern skies and none appear with such brilliance anywhere else on the planet.

Hence the decision to build this extraordinary complex of VLTs. At sunset, each one’s housing is opened and the four great telescopes are brought slowly into operation. Each machine is made to rotate and swivel, like football players stretching muscles before a match. Each housing is the size of a block of flats. Yet they move in complete silence, so precise is their engineering.

Read the entire article here.

Image: Architectural rendering of ESO’s planned European Extremely Large Telescope (E-ELT) shows the telescope at work, with its dome open and its record-setting 42-metre primary mirror pointed to the sky. Courtesy of the European Southern Observatory (ESO) / Wikipedia.

BigBang

Bert and Ernie and Friends

The universe is a very strange place, stranger than Washington D.C., stranger than most reality TV shows.

And, it keep getting stranger as astronomers and cosmologists continue to make ever more head-scratching discoveries. The latest, a pair of super-high energy neutrinos, followed by another 28. It seems that these tiny, almost massless, particles are reaching Earth from an unknown source, or sources, of immense power outside of our own galaxy.

The neutrinos were spotted by the IceCube detector, which is buried beneath about a mile of solid ice in an Antarctic glacier.

From i09:

By drilling a 1.5 mile hole deep into an Antarctic glacier, physicists working at the IceCube South Pole Observatory have captured 28 extraterrestrial neutrinos — those mysterious and extremely powerful subatomic particles that can pass straight through solid matter. Welcome to an entirely new age of astronomy.

Back in April of this year, the same team of physicists captured the highest energy neutrinos ever detected. Dubbed Bert and Ernie, the elusive subatomic particles likely originated from beyond our solar system, and possibly even our galaxy.

Neutrinos are extremely tiny and prolific subatomic particles that are born in nuclear reactions, including those that occur inside of stars. And because they’re practically massless (together they contain only a tiny fraction of the mass of a single electron), they can pass through normal matter, which is why they’re dubbed ‘ghost particles.’ Neutrinos are able to do this because they don’t carry an electric charge, so they’re immune to electromagnetic forces that influence charged particles like electrons and protons.

A Billion Times More Powerful

But not all neutrinos are the same. The ones discovered by the IceCube team are about a billion times more energetic than the ones coming out of our sun. A pair of them had energies above an entire petaelectron volt. That’s more than 1,000 times the energy produced by protons smashed at CERN’s Large Hadron Collider.

So whatever created them must have been extremely powerful. Like, mindboggingly powerful — probably the remnants of supernova explosions. Indeed, as a recent study has shown, these cosmic explosions are more powerful than we could have ever imagined — to the point where they’re defying known physics.

Other candidates for neutrino production include black holes, pulsars, galactic nuclei — or even the cataclysmic merger of two black holes.

That’s why the discovery of these 28 new neutrinos, and the construction of the IceCube facility, is so important. It’s still a mystery, but these new findings, and the new detection technique, will help.

Back in April, the IceCube project looked for neutrinos above one petaelectronvolt, which is how Bert and Ernie were detected. But the team went back and searched through their data and found 26 neutrinos with slightly lower energies, though still above 30 teraelectronvolts that were detected between May 2010 and May 2012. While it’s possible that some of these less high-energy neutrinos could have been produced by cosmic rays in the Earth’s atmosphere, the researchers say that most of them likely came from space. And in fact, the data was analyzed in such a way as to exclude neutrinos that didn’t come from space and other types of particles that may have tripped off the detector.

The Dawn of a New Field

“This is a landmark discovery — possibly a Nobel Prize in the making,” said Alexander Kusenko, a UCLA astroparticle physicist who was not involved in the IceCube collaboration. Thanks to the remarkable IceCube facility, where neutrinos are captured in holes drilled 1.5 miles down into the Antarctic glacier, astronomers have a completely new way to scope out the cosmos. It’s both literally and figuratively changing the way we see the universe.

“It really is the dawn of a new field,” said Darren Grant, a University of Alberta physicist, and a member of the IceCube team.

Read the entire article here.

BigBang, Technica

Above and Beyond

According to NASA, Voyager 1 officially left the protection of the solar system on or about August 25, 2013, and is now heading into interstellar space. It is now the first and only human-made object to leave the solar system.

Perhaps, one day in the distant future real human voyagers — or their android cousins — will come across the little probe as it continues on its lonely journey.

From Space:

A spacecraft from Earth has left its cosmic backyard and taken its first steps in interstellar space.

After streaking through space for nearly 35 years, NASA’s robotic Voyager 1 probe finally left the solar system in August 2012, a study published today (Sept. 12) in the journal Science reports.

“Voyager has boldly gone where no probe has gone before, marking one of the most significant technological achievements in the annals of the history of science, and as it enters interstellar space, it adds a new chapter in human scientific dreams and endeavors,” NASA science chief John Grunsfeld said in a statement. “Perhaps some future deep-space explorers will catch up with Voyager, our first interstellar envoy, and reflect on how this intrepid spacecraft helped enable their future.”

A long and historic journey

Voyager 1 launched on Sept. 5, 1977, about two weeks after its twin, Voyager 2. Together, the two probes conducted a historic “grand tour” of the outer planets, giving scientists some of their first up-close looks at Jupiter, Saturn, Uranus, Neptune and the moons of these faraway worlds.

The duo completed its primary mission in 1989, and then kept on flying toward the edge of the heliosphere, the huge bubble of charged particles and magnetic fields that the sun puffs out around itself. Voyager 1 has now popped free of this bubble into the exotic and unexplored realm of interstellar space, scientists say.

They reached this historic conclusion with a little help from the sun. A powerful solar eruption caused electrons in Voyager 1’s location to vibrate signficantly between April 9 and May 22 of this year. The probe’s plasma wave instrument detected these oscillations, and researchers used the measurements to figure out that Voyager 1’s surroundings contained about 1.3 electrons per cubic inch (0.08 electrons per cubic centimeter).

That’s far higher than the density observed in the outer regions of the heliosphere (roughly 0.03 electrons per cubic inch, or 0.002 electrons per cubic cm) and very much in line with the 1.6 electrons per cubic inch (0.10 electrons per cubic cm) or so expected in interstellar space. [Photos from NASA’s Voyager 1 and 2 Probes]

“We literally jumped out of our seats when we saw these oscillations in our data — they showed us that the spacecraft was in an entirely new region, comparable to what was expected in interstellar space, and totally different than in the solar bubble,” study lead author Don Gurnett of the University of Iowa, the principal investigator of Voyager 1’s plasma wave instrument, said in a statement.

It may seem surprising that electron density is higher beyond the solar system than in its extreme outer reaches. Interstellar space is, indeed, emptier than the regions in Earth’s neighborhood, but the density inside the solar bubble drops off dramatically at great distances from the sun, researchers said.

Calculating a departure date

The study team wanted to know if Voyager 1 left the solar system sometime before April 2013, so they combed through some of the probe’s older data. They found a monthlong period of electron oscillations in October-November 2012 that translated to a density of 0.004 electrons per cubic inch (0.006 electrons per cubic cm).

Using these numbers and the amount of ground that Voyager 1 covers — about 325 million miles (520 million kilometers) per year — the researchers calculated that the spacecraft likely left the solar system in August 2012.

That time frame matches up well with several other important changes Voyager 1 observed. On Aug. 25, 2012, the probe recorded a 1,000-fold drop in the number of charged solar particles while also measuring a 9 percent increase in fast-moving galactic cosmic rays, which originate beyond the solar system.

“These results, and comparison with previous heliospheric radio measurements, strongly support the view that Voyager 1 crossed the heliopause into the interstellar plasma on or about Aug. 25, 2012,” Gurnett and his colleagues write in the new study.

At that point, Voyager 1 was about 11.25 billion miles (18.11 billion km) from the sun, or roughly 121 times the distance between Earth and the sun. The probe is now 11.66 billion miles (18.76 billion km) from the sun. (Voyager 2, which took a different route through the solar system, is currently 9.54 billion miles, or 15.35 billion km, from the sun.)

Read the entire article here.

Image: Voyager Gold Disk. Courtesy of Wikipedia.

BigBang

Interstellar Winds of Change

First measured in the early-seventies, the interstellar wind is far from a calm, consistent breeze. Rather, as new detailed measurements show, it’s a blustery, fickle gale.

From ars technica:

Interstellar space—the region between stars in our galaxy—is fairly empty. There are still enough atoms in that space to produce a measurable effect as the Sun orbits the galactic center, however. The flow of these atoms, known as the interstellar wind, provides a way to study interstellar gas, which moves independently of the Sun’s motion.

A new analysis of 40 years of data showed that the interstellar wind has changed direction and speed over time, demonstrating that the environment surrounding the Solar System changes measurably as well. Priscilla Frisch and colleagues compared the results from several spacecraft, both in Earth orbit and interplanetary probes. The different positions and times in which these instruments operated revealed that the interstellar wind has increased slightly in speed. Additional measurements revealed that the flow of atoms has shifted somewhere between 4.4 degrees and 9.2 degrees. Both these results indicate that the Sun is traveling through a changing environment, perhaps one shaped by turbulence in interstellar space.

The properties of the Solar System are dominated by the Sun’s gravity, magnetic field, and the flow of charged particles outward from its surface. However, a small number of electrically neutral particles—mostly light atoms—pass through the Solar System. These particles are part of the local interstellar cloud (LIC), a relatively hot region of space governed by its internal processes.

Neutral helium is the most useful product of the interstellar wind flowing through the Solar System. Helium is abundant, comprising roughly 25 percent of all interstellar atoms. In its electrically neutral form, helium is largely unaffected by magnetic fields, both from the Sun and within the LIC. The present study also considered neutral oxygen and nitrogen atoms, which are far less abundant, but more massive and therefore less strongly jostled even than helium.

When helium atoms flow through the Solar System, their paths are curved by the Sun’s gravity depending on how quickly they are moving. Slower atoms are more strongly affected than faster ones, so the effect is a cone of particle trajectories. The axis of that focusing cone is the dominant direction of the interstellar wind, while the width of the cone indicates how much variation in particle speeds is present, a measure of the speed and turbulence in the LIC.

The interstellar wind was first measured in the 1970s by missions such as the Mariner 10 (which flew by Venus and Mercury) from the United States and the Prognoz 6 satellite from the Soviet Union. More recently, the Ulysses spacecraft in solar orbit, the MESSENGER probe studying Mercury, and the IBEX (Interstellar Boundary EXplorer) mission collected data from several perspectives within the Solar System.

Read the entire article here.

Image: Local interstellar cloud. Courtesy of NASA.

BigBang, Idea Soup

Name a Planet

So, you’d like to name a planet, perhaps after your grandmother or a current girlfriend or boyfriend. Here’s how below. But, forget trying to name a celestial object after your pet. So, “Mr.Tiddles”, “Snowy” and “Rex” are out.

From the Independent:

The international institute responsible for naming planets, stars and other celestial bodies has announced that the public will now be able to submit their own suggestions on what to call new discoveries in space.

Founded in 1919, the Paris-based International Astronomical Union (IAU) has more than 11,000 members in more than 90 countries, making it the de facto authority in the field.

Without any official laws enforcing the use of planetary names, the decisions on what to call new discoveries are usually a matter of consensus.

The changes announced by IAU hope to make public’s involvement more streamlined, asking that submissions are “sent to iaupublic@iap.fr” and promising that they will be “handled on a case-by-case basis”.

“The IAU fully supports the involvement of the general public, whether directly or through an independent organised vote, in the naming of planetary satellites, newly discovered planets, and their host stars,” says the statement.

The following guidelines have been offered for submission by would-be planet-namers:

? 16 characters or less in length,

? preferably one word,

? pronounceable (in as many languages as possible),

? non-offensive in any language or culture,

? not too similar to an existing name of an astronomical object.

? names of pet animals are discouraged,

? names of a purely or principally commercial nature are not allowed.

Despite this nod towards a democratic process, the IAU recently vetoed naming a newly discovered moon orbiting Pluto after Vulcan, the home-planet of Spock from the Star Trek franchise.

William Shatner, the actor who played Captain James Kirk in the show, launched a campaign via Twitter after the Seti institute discovered the new moons and created an online poll to name them.

Submitted names had to be picked from classical mythology and have an association with the underworld.‘Vulcan’ easily won the contest with 174,062 votes, followed by ‘Cerberus’ with 99,432 votes, and ‘Styx’ with 87,858 votes.

However, the IAU chose ‘Kerberus’ and ‘Styx’ as the names for the new moons, rejecting Vulcan as it “had already been used for a hypothetical planet between Mercury and the Sun.”

This planet was later found not to exist, but the term ‘vulcanoid’ is still used to refer to asteroids within the orbit of Mercury. Shatner responded to the IAU’s decision by tweeting, “They didn’t name the moon Vulcan. I’m sad. Who’d ever thought I’d be betrayed by geeks and nerds?”

 

Read the entire article here.

BigBang

The View From Saturn

As Carl Sagan would no doubt have had us remember, we are still collectively residents of a very small, very pale blue dot. The image of planet Earth was taken by the Cassini spacecraft, which has been busy circuiting and mapping the Saturnian system over the last several years. Cassini turned the attention of its cameras to our home on July 19, 2013 for this portrait.

From NASA:

Color and black-and-white images of Earth taken by two NASA interplanetary spacecraft on July 19 show our planet and its moon as bright beacons from millions of miles away in space.

NASA’s Cassini spacecraft captured the color images of Earth and the moon from its perch in the Saturn system nearly 900 million miles (1.5 billion kilometers) away. MESSENGER, the first probe to orbit Mercury, took a black-and-white image from a distance of 61 million miles (98 million kilometers) as part of a campaign to search for natural satellites of the planet.

In the Cassini images Earth and the moon appear as mere dots — Earth a pale blue and the moon a stark white, visible between Saturn’s rings. It was the first time Cassini’s highest-resolution camera captured Earth and its moon as two distinct objects.

It also marked the first time people on Earth had advance notice their planet’s portrait was being taken from interplanetary distances. NASA invited the public to celebrate by finding Saturn in their part of the sky, waving at the ringed planet and sharing pictures over the Internet. More than 20,000 people around the world participated.

“We can’t see individual continents or people in this portrait of Earth, but this pale blue dot is a succinct summary of who we were on July 19,” said Linda Spilker, Cassini project scientist, at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “Cassini’s picture reminds us how tiny our home planet is in the vastness of space, and also testifies to the ingenuity of the citizens of this tiny planet to send a robotic spacecraft so far away from home to study Saturn and take a look-back photo of Earth.”

Pictures of Earth from the outer solar system are rare because from that distance, Earth appears very close to our sun. A camera’s sensitive detectors can be damaged by looking directly at the sun, just as a human being can damage his or her retina by doing the same. Cassini was able to take this image because the sun had temporarily moved behind Saturn from the spacecraft’s point of view and most of the light was blocked.

A wide-angle image of Earth will become part of a multi-image picture, or mosaic, of Saturn’s rings, which scientists are assembling. This image is not expected to be available for several weeks because of the time-consuming challenges involved in blending images taken in changing geometry and at vastly different light levels, with faint and extraordinarily bright targets side by side.

“It thrills me to no end that people all over the world took a break from their normal activities to go outside and celebrate the interplanetary salute between robot and maker that these images represent,” said Carolyn Porco, Cassini imaging team lead at the Space Science Institute in Boulder, Colo. “The whole event underscores for me our ‘coming of age’ as planetary explorers.”

Read the entire article here.

Image: In this rare image taken on July 19, 2013, the wide-angle camera on NASA’s Cassini spacecraft has captured Saturn’s rings and our planet Earth and its moon in the same frame. Courtesy: NASA/JPL-Caltech/Space Science Institute.

BigBang

Our Beautiful Galaxy

We should post stunning images of the night sky like these more often. For most of us, unfortunately, light pollution from our surroundings hides beautiful vistas like these from the naked eye.

Image: Receiving the Galatic Beam. The Milky Way appears to line up with the giant 64-m dish of the radio telescope at Parkes Observatory in Australia. As can be seen from the artificial lights around the telescope, light pollution is not a problem for radio astronomers. Radio and microwave interference is a big issue however, as it masks the faint natural emissions from distant objects in space. For this reason many radio observatories ban mobile phone use on their premises. Courtesy: Wayne England / The Royal Observatory Greenwich / Telegraph.

BigBang, Environs

Earth as the New Venus

New research models show just how precarious our planet’s climate really is. Runaway greenhouse warming would make a predicted 2-6 feet rise in average sea levels over the next 50-100 years seem like a puddle at the local splash pool.

From ars technica:

With the explosion of exoplanet discoveries, researchers have begun to seriously revisit what it takes to make a planet habitable, defined as being able to support liquid water. At a basic level, the amount of light a planet receives sets its temperature. But real worlds aren’t actually basic—they have atmospheres, reflect some of that light back into space, and experience various feedbacks that affect the temperature.

Attempts to incorporate all those complexities into models of other planets have produced some unexpected results. Some even suggest that Earth teeters on the edge of experiencing a runaway greenhouse, one that would see its oceans boil off. The fact that large areas of the planet are covered in ice may make that conclusion seem a bit absurd, but a second paper looks at the problem from a somewhat different angle—and comes to the same conclusion. If it weren’t for clouds and our nitrogen-rich atmosphere, the Earth might be an uninhabitable hell right now.

The new work focuses on a very simple model of an atmosphere: a linear column of nothing but water vapor. This clearly doesn’t capture the complex dynamics of weather and the different amounts of light to reach the poles, but it does include things like the amount of light scattered back out into space and the greenhouse impact of the water vapor. These sorts of calculations are simple enough that they were first done decades ago, but the authors note that this particular problem hadn’t been revisited in 25 years. Our knowledge of how water vapor absorbs both visible and infrared light has improved over that time.

Water vapor, like other greenhouse gasses, allows visible light to reach the surface of a planet, but it absorbs most of the infrared light that gets emitted back toward space. Only a narrow window, centered around 10 micrometer wavelengths, makes it back out to space. Once the incoming energy gets larger than the amount that can escape, the end result is a runaway greenhouse: heat evaporates more surface water, which absorbs more infrared, trapping even more heat. At some point, the atmosphere gets so filled with water vapor that light no longer even reaches the surface, instead getting absorbed by the atmosphere itself.

The model shows that, once temperatures reach 1,800K, a second window through the water vapor opens up at about four microns, which allows additional energy to escape into space. The authors suggest that this could be used when examining exoplanets, as high emissions in this region could be taken as an indication that the planet was undergoing a runaway greenhouse.

The authors also used the model to look at what Earth would be like if it had a cloud-free, water atmosphere. The surprise was that the updated model indicated that this alternate-Earth atmosphere would absorb 30 percent more energy than previous estimates suggested. That’s enough to make a runaway greenhouse atmosphere stable at the Earth’s distance from the Sun.

So, why is the Earth so relatively temperate? The authors added a few additional factors to their model to find out. Additional greenhouse gasses like carbon dioxide and methane made runaway heating more likely, while nitrogen scattered enough light to make it less likely. The net result is that, under an Earth-like atmosphere composition, our planet should experience a runaway greenhouse. (In fact, greenhouse gasses can lower the barrier between a temperate climate and a runaway greenhouse, although only at concentrations much higher than we’ll reach even if we burn all the fossil fuels available.) But we know it hasn’t. “A runaway greenhouse has manifestly not occurred on post-Hadean Earth,” the authors note. “It would have sterilized Earth (there is observer bias).”

So, what’s keeping us cool? The authors suggest two things. The first is that our atmosphere isn’t uniformly saturated with water; some areas are less humid and allow more heat to radiate out into space. The other factor is the existence of clouds. Depending on their properties, clouds can either insulate or reflect sunlight back into space. On balance, however, it appears they are key to keeping our planet’s climate moderate.

But clouds won’t help us out indefinitely. Long before the Sun expands and swallows the Earth, the amount of light it emits will rise enough to make a runaway greenhouse more likely. The authors estimate that, with an all-water atmosphere, we’ve got about 1.5 billion years until the Earth is sterilized by skyrocketing temperatures. If other greenhouse gasses are present, then that day will come even sooner.

The authors don’t expect that this will be the last word on exoplanet conditions—in fact, they revisited waterlogged atmospheres in the hopes of stimulating greater discussion of them. But the key to understanding exoplanets will ultimately involve adapting the planetary atmospheric models we’ve built to understand the Earth’s climate. With full, three-dimensional circulation of the atmosphere, these models can provide a far more complete picture of the conditions that could prevail under a variety of circumstances. Right now, they’re specialized to model the Earth, but work is underway to change that.

Read the entire article here.

Image: Venus shrouded in perennial clouds of carbon dioxide, sulfur dioxide and sulfuric acid, as seen by the Messenger probe, 2004. Courtesy of Wikipedia.

BigBang

Cosmic portrait

Make a note in your calendar if you are so inclined: you’ll be photographed from space on July 19, 2013, sometime between 9.27 and 9.42 pm (GMT).

No, this is not another wacky mapping stunt courtesy of Google. Rather, NASA’s Cassini spacecraft, which will be somewhere in the vicinity of Saturn, will train its cameras on us for a global family portrait.

From NASA:

NASA’s Cassini spacecraft, now exploring Saturn, will take a picture of our home planet from a distance of hundreds of millions of miles on July 19. NASA is inviting the public to help acknowledge the historic interplanetary portrait as it is being taken.

Earth will appear as a small, pale blue dot between the rings of Saturn in the image, which will be part of a mosaic, or multi-image portrait, of the Saturn system Cassini is composing.

“While Earth will be only about a pixel in size from Cassini’s vantage point 898 million [1.44 billion kilometers] away, the team is looking forward to giving the world a chance to see what their home looks like from Saturn,” said Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “We hope you’ll join us in waving at Saturn from Earth, so we can commemorate this special opportunity.”

Cassini will start obtaining the Earth part of the mosaic at 2:27 p.m. PDT (5:27 p.m. EDT or 21:27 UTC) and end about 15 minutes later, all while Saturn is eclipsing the sun from Cassini’s point of view. The spacecraft’s unique vantage point in Saturn’s shadow will provide a special scientific opportunity to look at the planet’s rings. At the time of the photo, North America and part of the Atlantic Ocean will be in sunlight.

Unlike two previous Cassini eclipse mosaics of the Saturn system in 2006, which captured Earth, and another in 2012, the July 19 image will be the first to capture the Saturn system with Earth in natural color, as human eyes would see it. It also will be the first to capture Earth and its moon with Cassini’s highest-resolution camera. The probe’s position will allow it to turn its cameras in the direction of the sun, where Earth will be, without damaging the spacecraft’s sensitive detectors.

“Ever since we caught sight of the Earth among the rings of Saturn in September 2006 in a mosaic that has become one of Cassini’s most beloved images, I have wanted to do it all over again, only better,” said Carolyn Porco, Cassini imaging team lead at the Space Science Institute in Boulder, Colo. “This time, I wanted to turn the entire event into an opportunity for everyone around the globe to savor the uniqueness of our planet and the preciousness of the life on it.”

Porco and her imaging team associates examined Cassini’s planned flight path for the remainder of its Saturn mission in search of a time when Earth would not be obstructed by Saturn or its rings. Working with other Cassini team members, they found the July 19 opportunity would permit the spacecraft to spend time in Saturn’s shadow to duplicate the views from earlier in the mission to collect both visible and infrared imagery of the planet and its ring system.

“Looking back towards the sun through the rings highlights the tiniest of ring particles, whose width is comparable to the thickness of hair and which are difficult to see from ground-based telescopes,” said Matt Hedman, a Cassini science team member based at Cornell University in Ithaca, N.Y., and a member of the rings working group. “We’re particularly interested in seeing the structures within Saturn’s dusty E ring, which is sculpted by the activity of the geysers on the moon Enceladus, Saturn’s magnetic field and even solar radiation pressure.”

This latest image will continue a NASA legacy of space-based images of our fragile home, including the 1968 “Earthrise” image taken by the Apollo 8 moon mission from about 240,000 miles (380,000 kilometers) away and the 1990 “Pale Blue Dot” image taken by Voyager 1 from about 4 billion miles (6 billion kilometers) away.

Read the entire article here.

Image: This simulated view from NASA’s Cassini spacecraft shows the expected positions of Saturn and Earth on July 19, 2013, around the time Cassini will take Earth’s picture. Cassini will be about 898 million miles (1.44 billion kilometers) away from Earth at the time. That distance is nearly 10 times the distance from the sun to Earth. Courtesy: NASA/JPL-Caltech

BigBang

Revisiting Drake

In 1960 radio astronomer Frank Drake began the first systematic search for intelligent signals emanating from space. He was not successful, but his pioneering efforts paved the way for numerous other programs, including SETI (Search for Extra-Terrestrial Intelligence). The Drake Equation is named for him, and put simply, gives an estimate of the number of active, extraterrestrial civilizations with methods of communication in our own galaxy. Drake postulated the equation as a way to get the scientific community engaged in the search for life beyond our home planet.

The Drake equation is:

N = R^{\ast} \cdot f_p \cdot n_e \cdot f_{\ell} \cdot f_i \cdot f_c \cdot L

where:

N = the number of civilizations in our galaxy with which communication might be possible (i.e. which are on our current past light cone); and

R* = the average number of star formation per year in our galaxy

fp = the fraction of those stars that have planets

ne = the average number of planets that can potentially support life per star that has planets

fl = the fraction of planets that could support life that actually develop life at some point

fi = the fraction of planets with life that actually go on to develop intelligent life (civilizations)

fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space

L = the length of time for which such civilizations release detectable signals into space

Now, based on recent discoveries of hundreds of extra-solar planets, or exoplanets (those beyond our solar system), by the Kepler space telescope and other Earth-bound observatories, researchers are fine-tuning the original Drake Equation for the 21st century.

From the New Scientist:

An iconic tool in the search for extraterrestrial life is getting a 21st-century reboot – just as our best planet-hunting telescope seems to have died. Though the loss of NASA’s Kepler telescope is a blow, the reboot could mean we find signs of life on extrasolar planets within a decade.

The new tool takes the form of an equation. In 1961 astronomer Frank Drake scribbled his now-famous equation for calculating the number of detectable civilisations in the Milky Way. The Drake equation includes a number of terms that at the time seemed unknowable – including the very existence of planets beyond our solar system.

But the past two decades have seen exoplanets pop up like weeds, particularly in the last few years thanks in large part to the Kepler space telescope. Launched in 2009Movie Camera, Kepler has found more than 130 worlds and detected 3000 or so more possibles. The bounty has given astronomers the first proper census of planets in one region of our galaxy, allowing us to make estimates of the total population of life-friendly worlds across the Milky Way.

With that kind of data in hand, Sara Seager at the Massachusetts Institute of Technology reckons the Drake equation is ripe for a revamp. Her version narrows a few of the original terms to account for our new best bets of finding life, based in part on what Kepler has revealed. If the original Drake equation was a hatchet, the new Seager equation is a scalpel.

Seager presented her work this week at a conference in Cambridge, Massachusetts, entitled “Exoplanets in the Post-Kepler Era”. The timing could not be more prescient. Last week Kepler suffered a surprise hardware failure that knocked out its ability to see planetary signals clearly. If it can’t be fixed, the mission is over.

“When we talked about the post-Kepler era, we thought that would be three to four years from now,” co-organiser David Charbonneau of the Harvard-Smithsonian Center for Astrophysics said last week. “We now know the post-Kepler era probably started two days ago.”

But Kepler has collected data for four years, slightly longer than the mission’s original goal, and so far only the first 18 months’ worth have been analysed. That means it may have already gathered enough information to give alien-hunters a fighting chance.

The original Drake equation includes seven terms, which multiplied together give the number of intelligent alien civilisations we could hope to detect (see diagram). Kepler was supposed to pin down two terms: the fraction of stars that have planets, and the number of those planets that are habitable.

To do that, Kepler had been staring unflinchingly at some 150,000 stars near the constellation Cygnus, looking for periodic changes in brightness caused by a planet crossing, or transiting, a star’s face as seen from Earth. This method tells us a planet’s size and its rough distance from its host star.

Size gives a clue to a planet’s composition, which tells us whether it is rocky like Earth or gassy like Neptune. Before Kepler, only a few exoplanets had been identified as small enough to be rocky, because other search methods were better suited to spotting larger, gas giant worlds.

“Kepler is the single most revolutionary project that has ever been undertaken in exoplanets,” says Charbonneau. “It broke open the piggybank and rocky planets poured out.” A planet’s distance from its star is also crucial, because that tells us whether the temperature is right for liquid water – and so perhaps life – to exist.

But with Kepler’s recent woes, hopes of finding enough potentially habitable planets, or Earth twins, to satisfy the Drake equation have dimmed. The mission was supposed to run for three-and-a-half years, which should have been enough to pinpoint Earth-sized planets with years of a similar length. After the telescope came online, the mission team realised that other sun-like stars are more active than ours, and they bounce around too much in the telescope’s field of view. To find enough Earths, they would need seven or eight years of data.

Read the entire article here.

Image courtesy of the BBC. Drake Equation courtesy of Wikipedia.

BigBang

One Way Ticket to Mars

You would be rightfully mistaken for thinking this might be a lonesome bus trip to Mars, Pennsylvania or to the North American headquarters of Mars, purveyors of many things chocolaty including M&Ms, Mars Bars and Snickers, in New Jersey. This one way ticket is further afield, to the Red Planet, and comes from a company known as Mars One — estimated time of departure, 2023.

From the Guardian:

A few months before he died, Carl Sagan recorded a message of hope to would-be Mars explorers, telling them: “Whatever the reason you’re on Mars is, I’m glad you’re there. And I wish I was with you.”

On Monday, 17 years after the pioneering astronomer set out his hopeful vision of the future in 1996, a company from the Netherlands is proposing to turn Sagan’s dreams of reaching Mars into reality. The company, Mars One, plans to send four astronauts on a trip to the Red Planet to set up a human colony in 2023. But there are a couple of serious snags.

Firstly, when on Mars their bodies will have to adapt to surface gravity that is 38% of that on Earth. It is thought that this would cause such a total physiological change in their bone density, muscle strength and circulation that voyagers would no longer be able to survive in Earth’s conditions. Secondly, and directly related to the first, they will have to say goodbye to all their family and friends, as the deal doesn’t include a return ticket.

The Mars One website states that a return “cannot be anticipated nor expected”. To return, they would need a fully assembled and fuelled rocket capable of escaping the gravitational field of Mars, on-board life support systems capable of up to a seven-month voyage and the capacity either to dock with a space station orbiting Earth or perform a safe re-entry and landing.

“Not one of these is a small endeavour” the site notes, requiring “substantial technical capacity, weight and cost”.

Nevertheless, the project has already had 10,000 applicants, according to the company’s medical director, Norbert Kraft. When the official search is launched on Monday at the Hotel Pennsylvania in New York, they expect tens of thousands more hopefuls to put their names forward.

Kraft told the Guardian that the applicants so far ranged in age from 18 to at least 62 and, though they include women, they tended to be men.

The reasons they gave for wanting to go were varied, he said. One of three examples Kraft forwarded by email to the Guardian cited Sagan.

An American woman called Cynthia, who gave her age as 32, told the company that it was a “childhood imagining” of hers to go to Mars. She described a trip her mother had taken her on in the early 1990s to a lecture at the University of Wisconsin.

In a communication to Mars One, she said the lecturer had been Sagan and she had asked him if he thought humans would land on Mars in her lifetime. Cynthia said: “He in turn asked me if I wanted to be trapped in a ‘tin can spacecraft’ for the two years it would take to get there. I told him yes, he smiled, and told me in all seriousness, that yes, he absolutely believed that humans would reach Mars in my lifetime.”

She told the project: “When I first heard about the Mars One project I thought, this is my chance – that childhood dream could become a reality. I could be one of the pioneers, building the first settlement on Mars and teaching people back home that there are still uncharted territories that humans can reach for.”

The prime attributes Mars One is looking for in astronaut-settlers is resilience, adaptability, curiosity, ability to trust and resourcefulness, according to Kraft. They must also be over 18.

Professor Gerard ‘t Hooft, winner of the Nobel prize for theoretical physics in 1999 and lecturer of theoretical physics at the University of Utrecht, Holland, is an ambassador for the project. ‘T Hooft admits there are unknown health risks. The radiation is “of quite a different nature” than anything that has been tested on Earth, he told the BBC.

Founded in 2010 by Bas Lansdorp, an engineer, Mars One says it has developed a realistic road map and financing plan for the project based on existing technologies and that the mission is perfectly feasible. The website states that the basic elements required for life are already present on the planet. For instance, water can be extracted from ice in the soil and Mars has sources of nitrogen, the primary element in the air we breathe. The colony will be powered by specially adapted solar panels, it says.

In March, Mars One said it had signed a contract with the American firm Paragon Space Development Corporation to take the first steps in developing the life support system and spacesuits fit for the mission.

The project will cost a reported $6bn (£4bn), a sum Lansdorp has said he hopes will be met partly by selling broadcasting rights. “The revenue garnered by the London Olympics was almost enough to finance a mission to Mars,” Lansdorp said, in an interview with ABC News in March.

Another ambassador to the project is Paul Römer, the co-creator of Big Brother, one of the first reality TV shows and one of the most successful.

On the website, Römer gave an indication of how the broadcasting of the project might proceed: “This mission to Mars can be the biggest media event in the world,” said Römer. “Reality meets talent show with no ending and the whole world watching. Now there’s a good pitch!”

The aim is to establish a permanent human colony, according to the company’s website. The first team would land on the surface of Mars in 2023 to begin constructing the colony, with a team of four astronauts every two years after that.

The project is not without its sceptics, however, and concerns have been raised about how astronauts might get to the surface and establish a colony with all the life support and other requirements needed. There were also concerns over the health implications for the applicants.

Dr Veronica Bray, from the University of Arizona’s lunar and planetary laboratory, told BBC News that Earth was protected from solar winds by a strong magnetic field, without which it would be difficult to survive. The Martian surface is very hostile to life. There is no liquid water, the atmospheric pressure is “practically a vacuum”, radiation levels are higher and temperatures vary wildly. High radiation levels can lead to increased cancer risk, a lowered immune system and possibly infertility, she said.

To minimise radiation, the project team will cover the domes they plan to build with several metres of soil, which the colonists will have to dig up.

The mission hopes to inspire generations to “believe that all things are possible, that anything can be achieved” much like the Apollo moon landings.

“Mars One believes it is not only possible, but imperative that we establish a permanent settlement on Mars in order to accelerate our understanding of the formation of the solar system, the origins of life, and of equal importance, our place in the universe” it says.

Read the entire article following the jump.

Image: Panoramic View From ‘Rocknest’ Position of Curiosity Mars Rover. Courtesy of JPL / NASA.

BigBang

Idyllic Undeveloped Land: Only 1,200 Light Years Away

Humans may soon make their only home irreversibly uninhabitable. Fortunately, astronomers have recently discovered a couple of exo-planets capable of sustaining life. Unfortunately, they are a little too distant — using current technology it would take humans around 26 million years. But, we can still dream.

From the New York Times:

Astronomers said Thursday that they had found the most Earth-like worlds yet known in the outer cosmos, a pair of planets that appear capable of supporting life and that orbit a star 1,200 light-years from here, in the northern constellation Lyra.

They are the two outermost of five worlds circling a yellowish star slightly smaller and dimmer than our Sun, heretofore anonymous and now destined to be known in the cosmic history books as Kepler 62, after NASA’s Kepler spacecraft, which discovered them. These planets are roughly half again as large as Earth and are presumably balls of rock, perhaps covered by oceans with humid, cloudy skies, although that is at best a highly educated guess.

Nobody will probably ever know if anything lives on these planets, and the odds are that humans will travel there only in their faster-than-light dreams, but the news has sent astronomers into heavenly raptures. William Borucki of NASA’s Ames Research Center, head of the Kepler project, described one of the new worlds as the best site for Life Out There yet found in Kepler’s four-years-and-counting search for other Earths. He treated his team to pizza and beer on his own dime to celebrate the find (this being the age of sequestration). “It’s a big deal,” he said.

Looming brightly in each other’s skies, the two planets circle their star at distances of 37 million and 65 million miles, about as far apart as Mercury and Venus in our solar system. Most significantly, their orbits place them both in the “Goldilocks” zone of lukewarm temperatures suitable for liquid water, the crucial ingredient for Life as We Know It.

Goldilocks would be so jealous.

Previous claims of Goldilocks planets with “just so” orbits snuggled up to red dwarf stars much dimmer and cooler than the Sun have had uncertainties in the size and mass and even the existence of these worlds, said David Charbonneau of the Harvard-Smithsonian Center for Astrophysics, an exoplanet hunter and member of the Kepler team.

“This is the first planet that ticks both boxes,” Dr. Charbonneau said, speaking of the outermost planet, Kepler 62f. “It’s the right size and the right temperature.” Kepler 62f is 40 percent bigger than Earth and smack in the middle of the habitable zone, with a 267-day year. In an interview, Mr. Borucki called it the best planet Kepler has found.

Its mate, known as Kepler 62e, is slightly larger — 60 percent bigger than Earth — and has a 122-day orbit, placing it on the inner edge of the Goldilocks zone. It is warmer but also probably habitable, astronomers said.

The Kepler 62 system resembles our own solar system, which also has two planets in the habitable zone: Earth — and Mars, which once had water and would still be habitable today if it were more massive and had been able to hang onto its primordial atmosphere.

The Kepler 62 planets continue a string of breakthroughs in the last two decades in which astronomers have gone from detecting the first known planets belonging to other stars, or exoplanets, broiling globs of gas bigger than Jupiter, to being able to discern smaller and smaller more moderate orbs — iceballs like Neptune and, now, bodies only a few times the mass of Earth, known technically as super-Earths. Size matters in planetary affairs because we can’t live under the crushing pressure of gas clouds on a world like Jupiter. Life as We Know It requires solid ground and liquid water — a gentle terrestrial environment, in other words.

Kepler 62’s newfound worlds are not quite small enough to be considered strict replicas of Earth, but the results have strengthened the already strong conviction among astronomers that the galaxy is littered with billions of Earth-size planets, perhaps as many as one per star, and that astronomers will soon find Earth 2.0, as they call it — our lost twin bathing in the rays of an alien sun.

“Kepler and other experiments are finding planets that remind us more and more of home,” said Geoffrey Marcy, a longtime exoplanet hunter at the University of California, Berkeley, and Kepler team member. “It’s an amazing moment in science. We haven’t found Earth 2.0 yet, but we can taste it, smell it, right there on our technological fingertips.”

Read the entire article following the jump.

Image: The Kepler 62 system: homes away from home. Courtesy of JPL-Caltech/Ames/NASA.

BigBang

Looking for Alien Engineering Work

We haven’t yet found any aliens inhabiting exoplanets orbiting distant stars. We haven’t received any intelligently manufactured radio signals from deep space. And, unless you subscribe to the conspiracy theories surrounding Roswell Area 51, it’s unlikely that we’ve been visited by an extra-terrestrial intelligence.

Most reasonable calculations suggest that the universe should be teeming with life beyond our small, blue planet. So, where are all the aliens and why haven’t we been contacted yet? Not content to wait, some astronomers believe we should be looking for evidence of distant alien engineering projects.

From the New Scientist:

ALIENS: where are you? Our hopes of finding intelligent companionship seem to be constantly receding. Mars and Venus are not the richly populated realms we once guessed at. The icy seas of the outer solar system may hold life, but almost certainly no more than microbes. And the search for radio signals from more distant extraterrestrials has so frustrated some astronomers that they are suggesting we shout out an interstellar “Hello”, in the hope of prodding the dozy creatures into a response.

So maybe we need to think along different lines. Rather than trying to intercept alien communications, perhaps we should go looking for alien artefacts.

There have already been a handful of small-scale searches, but now three teams of astronomers are setting out to scan a much greater volume of space (see diagram). Two groups hope to see the shadows of alien industry in fluctuating starlight. The third, like archaeologists sifting through a midden heap on Earth, is hunting for alien waste.

What they’re after is something rather grander than flint arrowheads or shards of pottery. Something big. Planet-sized power stations. Star-girdling rings or spheres. Computers the size of a solar system. Perhaps even an assembly of hardware so vast it can darken an entire galaxy.

It might seem crazy to even entertain the notion of such stupendous celestial edifices, let alone go and look for them. Yet there is a simple rationale. Unless tool-users are always doomed to destroy themselves, any civilisation out there is likely to be far older and far more advanced than ours.

Humanity has already covered vast areas of Earth’s surface with roads and cities, and begun sending probes to other planets. If we can do all this in a matter of centuries, what could more advanced civilisations do over many thousands or even millions of years?

In 1960, the physicist Freeman Dyson pointed out that if alien civilisations keep growing and expanding, they will inevitably consume ever more energy – and the biggest source of energy in any star system is the star itself. Our total power consumption today is equivalent to about 0.01 per cent of the sunlight falling on Earth, so solar power could easily supply all our needs. If energy demand keeps growing at 1 per cent a year, however, then in 1000 years we’d need more energy than strikes the surface of the planet. Other energy sources, such as nuclear fusion, cannot solve the problem because the waste heat would fry the planet.

In a similar position, alien civilisations could start building solar power plants, factories and even habitats in space. With material mined from asteroids, then planets, and perhaps even the star itself, they could really spread out. Dyson’s conclusion was that after thousands or millions of years, the star might be entirely surrounded by a vast artificial sphere of solar panels.

The scale of a Dyson sphere is almost unimaginable. A sphere with a radius similar to that of Earth’s orbit would have more than a hundred million times the surface area of Earth. Nobody thinks building it would be easy. A single shell is almost certainly out, as it would be under extraordinary stresses and gravitationally unstable. A more plausible option is a swarm: many huge power stations on orbits that do not intersect, effectively surrounding the star. Dyson himself does not like to speculate on the details, or on the likelihood of a sphere being built. “We have no way of judging,” he says. The crucial point is that if any aliens have built Dyson spheres, there is a chance we could spot them.

A sphere would block the sun’s light, making it invisible to our eyes, but the sphere would still emit waste heat in the form of infrared radiation. So, as Carl Sagan pointed out in 1966, if infrared telescopes spot a warm object but nothing shows up at visible wavelengths, it could be a Dyson sphere.

Some natural objects can produce the same effect. Very young and very old stars are often surrounded by dust and gas, which blocks their light and radiates infrared. But the infrared spectrum of these objects should be a giveaway. Silicate minerals in dust produce a distinctive broad peak in the spectrum, and molecules in a warm gas would produce bright or dark spectral lines at specific wavelengths. By contrast, waste heat from a sphere should have a smooth, featureless thermal spectrum. “We would be hoping that the spectrum looks boring,” says Matt Povich at the California State Polytechnic University in Pomona. “The more boring the better.”

Our first good view of the sky at the appropriate wavelengths came when the Infrared Astronomical Satellite surveyed the skies for 10 months in 1983, and a few astronomers have sifted through its data. Vyacheslav Slysh at the Space Research Institute in Moscow made the first attempt in 1985, and Richard Carrigan at Fermilab in Illinois published the latest search in 2009. “I wanted to get into the mode of the British Museum, to go and look for artefacts,” he says.

Carrigan found no persuasive sources, but the range of his search was limited. It would have detected spheres around sunlike stars only within 1000 light years of Earth. This is a very small part of the Milky Way, which is 100,000 light years across.

One reason few have joined Carrigan in the hunt for artefacts is the difficulty of getting funding for such projects. Then last year, the Templeton Foundation – an organisation set up by a billionaire to fund research into the “big questions” – invited proposals for its New Frontiers programme, specifically requesting research that would not normally be funded because of its speculative nature. A few astronomers jumped at the chance to look for alien contraptions and, in October, the programme approved three separate searches. The grants are just a couple of hundred thousand dollars each, but they do not have to fund new telescopes, only new analysis.

One team, led by Jason Wright at Pennsylvania State University in University Park, will look for the waste heat of Dyson spheres by analysing data from two space-based infrared observatories, the Wide-field Infrared Survey Explorer (WISE) and the Spitzer space telescope, launched in 2009 and 2003. Povich, a member of this team, is looking specifically within the Milky Way. Thanks to the data from Spitzer and WISE, Povich should be able to scan a volume of space thousands of times larger than previous searches like Carrigan’s. “For example, if you had a sun-equivalent star, fully enclosed in a Dyson sphere, we should be able to detect it almost anywhere in the galaxy.”

Even such a wide-ranging hunt may not be ambitious enough, according to Wright. He suspects that interstellar travel will prove no harder than constructing a sphere. An alien civilisation with such a high level of technology would spread out and colonise the galaxy in a few million years, building spheres as they go. “I would argue that it’s very hard for a spacefaring civilisation to die out. There are too many lifeboats,” says Wright. “Once you have self-sufficient colonies, you will take over the galaxy – you can’t even try to stop it because you can’t coordinate the actions of the colonies.”

If this had happened in the Milky Way, there should be spheres everywhere. “To find one or a few Dyson spheres in our galaxy would be very strange,” says Wright.

Read the entire article after the jump.

Image: 2001: A Space Odyssey, The Monolith. Courtesy of Daily Galaxy.