What Do You See When SETI’s Allen Telescope Array Is Aimed At The Sun?

A comparison between an observation of the sun using the ATA's 2.75 GHz band (left) and SOHO's 195A filter. Both are near-simultaneous observations on Oct. 1, 2009 (Saint-Hilaire et al., 2011)

A comparison between an observation of the sun using the ATA's 2.75 GHz band (left) and SOHO's 195A filter. Both are near-simultaneous observations on Oct. 1, 2009 (Saint-Hilaire et al., 2011).

And no, “aliens” isn’t the answer.

The Allen Telescope Array (ATA), located near Hat Creek, California, isn’t only used by the SETI Institute to seek out signals from extraterrestrial civilizations. The 42 6.1-meter antennae form an interferometer that can be used for a variety of astronomical studies — in reality, this is the main focus of the project. SETI studies “piggyback” the active astronomical research, passively collecting data.

Due to the radio interferometer’s wide field of view, one surprising use of the ATA is solar astronomy — at radio frequencies. The ATA can be used to simultaneously observe the whole of the solar disk at a range of frequencies rarely studied. As outlined in a recent arXiv publication, a University of California, Berkeley, team of astronomers headed by Pascal Saint-Hilaire have carried out the first ATA solar study, producing images of the sun in a light we rarely see it in (shown above).

According to the paper, active regions were observed at radio and microwave frequencies, spotting the emissions associated with bremsstrahlung — electromagnetic radiation generated by accelerated charged particles caught in intense magnetic fields, a feature typical inside solar active regions. Also, coronal interactions, or gyroresonance, between solar plasma and plasma waves (propagating along magnetic field lines) was detected.

Combining the ATA’s wide field of view, range of frequencies and high resolution, it looks like the ATA is the only solar radiotelescope on the planet.

For more on this fascinating study, read “Allen Telescope Array Multi-Frequency Observations of the Sun,” Saint-Hilaire et al., 2011. arXiv:1111.4242v1 [astro-ph.SR]

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Could Kepler Detect Borg Cubes? Why Not.

That's no sunspot.

"That's no sunspot."

Assuming Star Trek‘s Borg Collective went into overdrive and decided to build a huge cube a few thousand miles wide, then yes, the exoplanet-hunting Kepler space telescope should be able to spot it. But how could Kepler distinguish a cube from a nice spherical exoplanet?

With the help of Ray Villard over at Discovery News, he did some digging and found a paper dating back to 2005 — long before Kepler was launched. However, researcher Luc Arnold, of the Observatoire de Haute-Provence in Paris, did have the space telescope in mind when he studied what it would take to distinguish different hypothetical shapes as they passed in front of his theoretical stars.

The big assumption when looking for exoplanets that drift between distant stars and the Earth — events known as “transits” — is that the only shape these detectable exoplanets come in are spheres. Obvious really.

As a world passes in front of its parent star, a circular shadow will form. However, from Earth, we’d detect a slight dimming of the star’s “light curve” during the transit, allowing astronomers to deduce the exoplanet’s orbital period and size.

The transit method has been used to confirm the presence of hundreds of exoplanets so far, and Kepler has found over 1,200 additional exoplanet candidates. But say if astronomers paid closer attention to the shape of the received light curve; spherical objects have a distinct signature, but say if something looked different in the transiting “planet’s” light curve? Well, it could mean that something non-spherical has passed in front of a star. And what does that mean? Well, that would be a pretty convincing argument for the presence of a huge planet-sized artificial structure orbiting another star. Artifical structure = super-advanced alien civilization.

Arnold tested his theory that all manner of shapes could be detected by Kepler, assuming the transiting structure was on the scale of a few thousand miles wide. In this case, Arnold was testing his hypothesis to see whether we could detect an advanced civilization’s “shadow play.” Perhaps, rather than beaming messages by radio waves, an advanced civilization might want to signal their presence — SETI style — by blocking their sun’s light with vast sheets of lightweight material. As the shape passes in front of the star, the slight dimming of starlight would reveal an artificial presence in orbit.

By putting a series of these shapes into orbit, the aliens could create a kind of interstellar Morse code.

Of course, this is a rather “out there” idea, but I find it fascinating that Kepler could detect an alien artifact orbiting a star tens or hundreds of light-years away. Although this research is only considering orbital “billboards,” I quite like the idea that Kepler might also be able to detect a large structure like… I don’t know… a big Borg mothership. Having advanced warning of the presence of an aggressive alien race sitting on our cosmic doorstep — especially ones of the variety that like to assimilate — would be pretty handy.

Publication: Transit Lightcurve Signatures of Artificial Objects, L. Arnold, 2005. arXiv:astro-ph/0503580v1

Screaming Exoplanets: Detecting Alien Magnetospheres

Exoplanets may reveal their location through radio emissions (NASA)

Exoplanets may reveal their location through radio emissions (NASA)

In 2009, I wrote about a fascinating idea: in the hunt for “Earth-like” exoplanets, perhaps we could detect the radio emissions from a distant world possessing a magnetosphere. This basically builds on the premise that planets in the solar system, including Earth, generate electromagnetic waves as space plasma interacts with their magnetospheres. In short, with the right equipment, could we “hear” the aurorae on extra-solar planets?

In the research I reviewed, the US Naval Research Laboratory scientist concluded that he believed it was possible, but the radio telescopes we have in operation aren’t sensitive enough to detect the crackle of distant aurorae. According to a new study presented at the RAS National Astronomy Meeting in Llandudno, Wales, on Monday, this feat may soon become a reality, not for “Earth-like” worlds but for “Jupiter-like” worlds.

“This is the first study to predict the radio emissions by exoplanetary systems similar to those we find at Jupiter or Saturn,” said Jonathan Nichols of the University of Leicester. “At both planets, we see radio waves associated with auroras generated by interactions with ionised gas escaping from the volcanic moons, Io and Enceladus. Our study shows that we could detect emissions from radio auroras from Jupiter-like systems orbiting at distances as far out as Pluto.”

Rather than looking for the magnetospheres of Earth-like worlds — thereby finding exoplanets that have a protective magnetosphere that could nurture alien life — Nichols is focusing on larger, Jupiter-like worlds that orbit their host stars from a distance. This is basically another tool in the exoplanet-hunters’ toolbox.

Over 500 exoplanets have been confirmed to exist around other stars, and another 1,200 plus exoplanetary candidates have been cataloged by the Kepler Space Telescope. The majority of the confirmed exoplanets were spotted using the “transit method” (when the exoplanet passes in front of its host star, thereby dimming its light for astronomers to detect) and the “wobble method” (when the exoplanet gravitationally tugs on its parent star, creating a very slight shift in the star’s position for astronomers to detect), but only exoplanets with short orbital periods have been spotted so far.

The more distant the exoplanet from its host star, the longer its orbital period. To get a positive detection, it’s easy to spot an exoplanet with an orbital period of days, weeks, months, or a couple of years, but what of the exoplanets with orbits similar to Jupiter (12 years), Saturn (30 years) or even Pluto (248 years!)? If we are looking for exoplanets with extreme orbits like Pluto’s, it would be several generations-worth of observations before we’d even get a hint that a world lives there.

“Jupiter and Saturn take 12 and 30 years respectively to orbit the Sun, so you would have to be incredibly lucky or look for a very long time to spot them by a transit or a wobble,” said Nichols.

By assessing how the radio emissions for a Jupiter-like exoplanet respond to its rotation rate, the quantity of material falling into the gas giant from an orbiting moon (akin Enceladus’ plumes of water ice and dust being channeled onto the gas giant) and the exoplanet’s orbital distance, Nichols has been able to identify the characteristics of a possible target star. The hypothetical, “aurora-active” exoplanet would be located between 1 to 50 AU from an ultraviolet-bright star and it would need to have a fast spin for the resulting magnetospheric activity to be detectable at a distance of 150 light-years from Earth.

What’s more, the brand new LOw Frequency ARray (LOFAR) radio telescope should be sensitive enough to detect aurorae on Jupiter-like exoplanets, even though the exoplanets themselves are invisible to other detection methods. Nice.

As we’re talking about exoplanets, magnetospheres and listening for radio signals, let’s throw in some alien-hunting for good measure: “In our Solar System, we have a stable system with outer gas giants and inner terrestrial planets, like Earth, where life has been able to evolve. Being able to detect Jupiter-like planets may help us find planetary systems like our own, with other planets that are capable of supporting life,” Nichols added.

Although Nichols isn’t talking about directly detecting habitable alien worlds (just that the detection of Jupiter-like exoplanets could reveal Solar System-like star systems), I think back to the 2009 research that discusses the direct detection of habitable worlds using this method: Aliens, if you’re out there, you can be as quiet as you like (to avoid predators), but the screaming radio emissions from your habitable planet’s magnetosphere will give away your location…

The Ultimate Paternity Test: Are We Martian?

"Dad?" A scene from War of the Worlds.

This rather outlandish, sci-fi notion comes straight from the fertile minds of researchers from MIT, the Massachusetts General Hospital and Harvard University who are proposing a biology experiment that could be sent on a future Mars surface mission. If their hypothesis is proven, we wouldn’t only have an answer for the age old question: Are we alone? but we’d also have an answer for the not-so-age-old question: Did life from Mars spawn life on Earth?

The idea goes like this: countless tons of material from Mars has landed on Earth. We know this to be true; meteorites have been discovered on Earth that originate from the Red Planet. These rocks were blasted from the Martian surface after eons of asteroid impacts, and the rocks then drifted to Earth.

If there was once life on Mars — a concept that isn’t that far-fetched, considering Mars used to boast liquid water in abundance on its surface — then perhaps some tiny organisms (not dislike the hardy cyanobacteria that is thought to have been one of the earliest forms of life to evolve on our planet) hitched a ride on these rocks. If some of these organisms survived the harsh conditions during transit from Mars to Earth and made it though the searing heat as the meteorite fell through our atmosphere, then perhaps (perhaps!) that is what sparked life on Earth.

You may have heard a few variations of this mechanism, it is of course the “panspermia” hypothesis. Panspermia assumes that life isn’t exclusive to just one rocky body like Earth, perhaps life has the ability to hop from one planet to the next, helped on its way by asteroid impacts. Not only that, but perhaps (perhaps!) tiny microorganisms could drift, encased in interstellar dust, akin to pollen drifting in the wind, seeding distant star systems.

Naturally, when considering the distance between the planets (let alone the light-years between the stars!), one might be a little skeptical of panspermia. But it certainly would help us understand how life first appeared on Earth. After all, it’s not as if the solar system has a natural quarantine system in place — if Mars had (or has) bacteria on its surface, perhaps they have been spread to Earth, like an interplanetary flu bug. Also, as experiments are showing us, microorganisms have an uncanny ability to survive in space for extended periods of time.

So, according to my esteemed Discovery News colleague Ray Villard, the MIT team led by Christopher Carr and Maria Zuber and Gary Ruvkun, a molecular biologist at the Massachusetts General Hospital and Harvard University, are proposing to build an instrument to send to Mars. But this instrument won’t be looking for signs of life, it will be testing the hypothetical Martian DNA and RNA. Should this interplanetary paternity test prove positive, proving a relationship between Earth Brand™ Life and Mars Brand™ Life, then this could be proof of some extraterrestrial cross-pollination.

Although this is complete conjecture at this time, as there is no proof that life has ever existed on Mars (despite what research in dodgy research journals tell us), it is certainly an interesting idea that would not only test the hypothesis of panspermia, but also give us a clue about the potential human colonization of Mars.

To quote Ray:

This could give us pause about sending humans to a germ-laden alien world. It would be an ironic twist on the H.G. Wells classic 1898 novel “The War of the Worlds,” where invading Martians succumb to the common cold from Earth microbes.

See, Wells’ Martian warriors should have done genome testing first.

The Day Aliens Invaded… [UPDATE]

UPDATE (Mon. 9:50 a.m. PT): Shocker. NASA refutes Hoover’s claims. Apparently his paper failed peer review for publication in the International Journal of Astrobiology… in 2007! More here: “NASA Refutes Alien Discovery Claim — Discovery News

Original post: On Saturday, a NASA astrobiologist announced his “irrefutable proof” that aliens — the size of bacteria — exist. Using a sophisticated electron microscope, Richard Hoover looked deep into meteorite samples to see complex fossilized microscopic structures that looked suspiciously like bacteria found here on Earth.

Some of the suspect alien microorganisms even resemble cyanobacteria, a basic microorganism that helped make early-Earth hospitable to life by producing oxygen. Cyanobacteria can live in space for extended periods of time; tests on the International Space Station have shown the single-celled specks are hardy little buggers, surviving in a kind of “suspended animation,” sleeping for months (even years) in vacuous, frozen, high-radiation conditions. When brought back to Earth, the critters come back to life.

Needless to say, when Hoover announced this discovery of “alien” microbes, I wasn’t the only one who was thinking panspermia, the hypothetical mechanism where life — in the form of a microbe like cyanobacteria — hops from one planet to the next encased inside meteoroids.

Is this really proof of aliens? Is it evidence for panspermia? Does this mean life on Earth may have been seeded by alien microbes stowing away inside chunks of space rock? Does mankind need to invent an anti(alien)bacterial handwash?! (I’ve watched The Andromeda Strain.)

As mentioned in my Discovery News article on the subject, I’m skeptical about Hoover’s claims. This isn’t because I think Hoover’s work is rubbish (I have yet to finish digesting his lengthy paper), it’s just the way he decided to publish his work. The online Journal of Cosmology isn’t exactly the best place to submit your paper if you want your research to be taken seriously. And why the hell he gave FOX News the “exclusive,” I have no idea.

Sure, Hoover has discovered some odd-looking, alien-looking, bacteria-sized shapes in meteorite samples (he’s even done some interesting chemical analysis on the micro-“fossils”), but he’s going to have to do a far better job at convincing the scientific community that they are extraterrestrials.

Personally, I think these dinky “fossils” are a little too well preserved. Perhaps a far simpler explanation can be found? *cough* Contamination. *cough*

I’d love to know what NASA’s official line is, they seem to be staying remarkably quiet considering one of their employees has just announced the discovery of ET…

Read more: “Has Evidence for Alien Life Been Found?

Dead On Arrival: Necropanspermia Spawned Life on Earth?

Are those Martian fossils in meteorite ALH84001? (NASA)

Are those Martian fossils in meteorite ALH84001? (NASA)

Panspermia” is a hypothesis that life is transferred from planet-to-planet and star system-to-star system through some interplanetary or interstellar means.

But for panspermia to work, this life needs to be sufficiently protected — and, um, kept alive — from the worst the universe can throw at it (such as radiation, cold and vacuum). Alas, when considering interstellar hops, the timescales are likely too long (i.e. millions of years) and said life will be dead on arrival.

We know that Earth Brand™ life is a pretty hardy thing. After all, we’ve tortured terrestrial microbes and mosquito larvae in the vacuum of space to see if they’d pop. Sure enough, when brought back to terra firma the various creatures wriggled and squirmed as if nothing had happened. But these experiments in orbit were carried out over the course of months or years. While this might be suitable for interplanetary transfers, it would take millions of years for an extraterrestrial interloper to traverse even a modest interstellar gap.

Any hitchhikers that were alive on a stellar wind-blown particle will be toast (or, more accurately: freeze-dried, pulverized, mashed-up, DNA-shredded mess) on reaching their exotic destination eons later.

What good are tiny alien fossils when the panspermia model is supposed to seed other worlds with life… that’s actually alive?

Enter a new incarnation of pansermia: “Necropanspermia.”

Conceived by Paul Wesson, of Herzberg Institute of Astrophysics in Canada, necropanspermia is the transfer of the information of life to new worlds, wriggling extraterrestrial bacterium not required.

Assuming alien microbial life has made the trip across interstellar space, died and then fossilized, Wesson reckons the information contained within the long-dead microbe could be used as some kind of template by a hospitable world to use and grow new life. (It’s not quite zombie science, but it’s hard not to say “reanimated alien corpse.”)

Wesson even goes so far to suggest ET’s microbial remains can be “resurrected.”

“Resurrection may, however, be possible.” Wesson concludes in his Space Science Reviews paper. “Certain micro-organisms possess remarkably effective enzyme systems that can repair a multitude of strand breaks.”

Hypothesizing about various forms of panspermia may seem more like a philosophical argument, but Wesson suggests that we might be able to find evidence for necropanspermia if we collect some dust samples from the outermost reaches of the solar system, far enough away from Earth’s biological pollution.

Alas, as the Hayabusa asteroid mission has proven, capturing dust from anywhere in space isn’t easy.

Read more about necropanspermia in my Discovery News article “Life on Earth Spawned by Dead Alien Microbes?

Was Voyager 2 Hijacked by Aliens? No.

The Voyager 2 spacecraft has been speeding through the Solar System since 1977 and it’s seen a lot. Besides scooting past Jupiter, Saturn, Uranus and Neptune, the probe is now passing through the very limit of the heliosphere (called the heliopause) where it has begun to detect a magnetic field beyond the Solar System. The fact we have man-made objects exiting our star system is something that makes me goosebumpily.

For some perspective, Voyager 2 is so far away from Earth that it takes nearly 13 hours for commands sent from Earth to reach the probe.

After decades of travel, the NASA spacecraft continues to relay data back to us, making it one of the most profound and exciting space missions ever launched. Perhaps unsurprisingly, the aging explorer recently experienced a glitch and the data received by NASA was rather garbled.

Naturally, the conspiracy theorists were out in force quickly pointing their sticky fingers at a possible encounter of the 3rd kind. How these ‘aliens’ found the probe in the first place and reprogrammed the transmission for it to appear corrupt Earth-side is beyond me, but according to an ‘expert’ in Germany, aliens (with an aptitude for reprogramming 30 year old Earth hardware, presumably) were obviously to blame.

One of the alien implication articles came from yet another classic ‘science’ post thrown together by the UK’s Telegraph where they decided to take the word of a UFO expert (obviously a viable source) without any kind of counter-argument from a real expert of real science. (But this is the same publication that brought us other classics such as the skull on Mars and the Doomsday Turkey, so it’s not too surprising.)

As I discussed in a recent CRI English radio debate with Beyond Beijing hosts Chris Gelken and Xu Qinduo, the Voyager-alien implication is beyond funny; an entertaining sideline to poke fun at while NASA worked out what actually went wrong. But the big difference was that Chris and Xu had invited Seth Shostak (from the SETI Institute) and Douglas C. Lin (from the Kavli Institute for Astronomy and Astrophysics at Peking University) to join the fun. No UFO expert in sight, so the discussion was biased toward science and logic, not crazy talk.

(It was an awesome show by the way, and you can check out the recording via my Discovery News article.)

So what did happen to Voyager 2? It turns out that aliens are not required to answer this cosmic mystery.

On Tuesday, NASA announced that Voyager 2 had flipped one of its bits of memory the wrong way. “A value in a single memory location was changed from a 0 to a 1,” said JPL’s Veronia McGregor.

This glitch was thought to occur in the flight data system, which formats information for transmission to Earth. Should something go wonky in its memory allocation, the stuff it transmits can be turned into gibberish.

Although it isn’t known how this single bit was flipped (and we may never know, as Voyager 2 is an awful long way from home), it sounds very much like a cosmic ray event interfering with the onboard electronics. As cosmic rays are highly energetic charged particles, they can penetrate deep into computer systems, causing an error in calculations.

And this situation isn’t without precedent either. Recently, NASA’s Mars Reconnaissance Orbiter (MRO) was hit by a cosmic ray event, causing the onboard computer to switch to “safe mode.” Also, Voyager 2 is beginning to exit the Sun’s outermost sphere of influence, where turbulence and confused magnetic fields rule. If I had to guess, I’d say — statistically-speaking — the probe might have a greater chance of being hit by the most energetic cosmic rays from deep space.

Just because something “mysterious” happens in space doesn’t mean aliens, the Illuminati or some half-baked doomsday phenomenon caused it. Before jumping to conclusions it would be nice if certain newspapers and UFO experts alike could look at the most likely explanation before pulling the alien card.

Alas, I suspect that some things will never change.