Want to Feel Good? Watch the Aurora Borealis in HD

The Aurora from Terje Sorgjerd on Vimeo.

I actually posted this jaw-dropping video on Discovery News last month, but today it got picked up on Digg, so I was reminded why I had to feature it.

The video is actually composed of 22,000 high-definition photographs, stitched together is a finely crafted time lapse video. The photographer in question is Terje Sorgjerd who braved -22C temperatures in the Arctic Circle to bring us this stunning perspective of the Aurora Borealis, or the Northern Lights. Throw in the Hans Zimmer “Gladiator” theme tune “Now We Are Free” and we get a timeless classic video that can be watched over and over again and never get bored.

So, sit back and enjoy the Sun-Earth interaction at its most spectacular.

For more of Sorgjerd’s work, check out his Facebook page.

Special thanks to my good friend Geir Barstein, science journalist at the Norwegian newspaper Dagbladet for originally writing about Sorgjerd’s work.

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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.

When Stardust Met Tempel, a Love Story

Comet Tempel 1 near Stardust-NExT close approach (NASA)

Comet Tempel 1 near Stardust-NExT close approach (NASA)

A NASA spacecraft, a lonely comet and a Valentine’s date with no comparison.

Last night, NASA’s veteran Stardust-NExT mission successfully visited its second comet, Tempel 1. Having already been visited by NASA’s Deep Impact mission in 2005, it’s hard not to wonder whether Tempel 1 was a little apprehensive. Deep Impact did lob a refrigerator-sized copper impactor into the comet’s surface during the 2005 encounter, so I think we can forgive the comet some pre-date jitters.

Fortunately, Stardust was the perfect date (no impactors, silverware, dishes or bottles were thrown), just a peaceful flyby, during which the spacecraft beamed dozens of photos back to Earth. To quote Joe Veverka, Stardust-NExT principal investigator: “It was 1,000 percent successful!”

Alas, although the date was a success, there won’t be the sound of wedding bells any time soon. Stardust is now powering away from the comet at a breakneck speed. Was it something Tempel 1 said?

For more on this Valentine’s rendezvous, have a read of my Discovery News article “Stunning Photos from a Comet Near-Kiss.”

Oh yes, and I got bored, so I created a rough animation of the flyby. Enjoy!

Can Spicules Explain the Mysteries of Coronal Heating?

Solar spicules as imaged by NASA's Solar Dynamics Observatory (NASA)

Solar spicules as imaged by NASA's Solar Dynamics Observatory (NASA)

There’s one recurring question I’ve been asking for nearly a decade: Why is the Sun’s corona (its atmosphere) so hot?

When asking this out loud I inevitably get the sarcastic “um, because the Sun is… hot?” reply. Yes, the Sun is hot, really hot, but solar physicists have spent the last half-century trying to understand why the corona is millions of degrees hotter than the solar surface.

After all, if the air surrounding a light bulb was a couple of magnitudes hotter than the bulb’s surface, you’d want to know why that’s the case, right? At first glance, the solar atmosphere is breaking all kinds of thermodynamic laws.

The Sun is a strange beast and because of its magnetic dominance, energy travels through the solar body in rather unfamiliar ways. And today, a group of solar physicists have put forward a new theory as to where the coronal energy is coming from. But they’ve only been able to do this with help from NASA’s newest and most advanced solar telescope: the Solar Dynamics Observatory, or SDO.

Using the SDO’s high-definition cameras and imagery from the awesome Japanese Hinode solar observatory, features previously invisible to solar astronomers have been resolved. The features in question are known as “spicules.” These small-scale jets inject solar plasma from the solar surface into the lower corona, but until now they’ve been considered too cool to have any appreciable heating effect.

That was until a new type of hot, high-speed spicule was discovered.

“It’s a little jet, then it takes off,” solar physicist Scott McIntosh, of the National Center for Atmospheric Research’s High Altitude Observatory, told Discovery News’ Larry O’Hanlon. “What we basically find is that the connection is the heated blobs of plasma. It’s kind of a missing link that we’ve been looking for since the 1960s.”

These Type II spicules blast hot multi-million degree Kelvin plasma at speeds of 100 to 150 kilometers per second (62 to 93 miles per second) into the corona and then dissipate. What’s more, these aren’t isolated events, they’ve been observed all over the Sun. “This phenomenon is truly ubiquitous and populates the solar wind,” said McIntosh.

While this research provides more clarity on coronal dynamics, McIntosh is keen to point out that Type II spicules probably don’t tell the whole coronal heating story.

NASA’s coronal physics heavyweight James Klimchuk agrees. “It is very nice work, but it is absolutely not the final story on the origin of hot coronal plasma,” he said.

“Based on some simple calculations I have done, spicules account for only a small fraction of the hot plasma.”

Klimchuk favors coronal heating through magnetic stresses in the lower atmosphere generating small reconnection events. Right at the base of the corona, loops of magnetic flux channeling multi-million degree plasma high above the Sun’s chromosphere become stressed and eventually snap. These reconnection processes produce sub-resolution nanoflare events — akin to small explosions releasing energy into the solar plasma, heating it up.

Another heating mechanism — a mechanism I studied during my solar research days (.pdf) — is that of wave heating, when magnetohydrodynamic waves (I studied high-frequency Alfven waves, or ion cyclotron waves) interact with the lower corona, heating it up.

But which heating mechanism injects the most energy into the corona? For now, although there’s plenty of theorized processes (including these new transient Type II spicules), we don’t really know. We can only observe the solar corona from afar, so getting a true grasp on coronal dynamics is very hard. We really need a probe to dive deep into the solar atmosphere and take a measurement in-situ. Although the planned Solar Probe Plus will provide some answers, it may still be some time before we know why the corona is so hot.

But it is most likely that it’s not one coronal heating mechanism, but a combination of the above and, perhaps, a mechanism we haven’t uncovered yet.

For more on this fascinating research, check out Larry O’Hanlon’s Discovery News article “New Clue May Solve Solar Mystery.”

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?

Compex Magnetic Eruption Witnessed by Solar Observatories

Solar Dynamics Observatory view of the solar disk shortly after eruption (NASA).

This morning, at 08:55 UT, NASA’s Solar Dynamics Observatory (SDO) detected a C3-class flare erupt inside a sunspot cluster. 100,000 kilometers away, deep within the solar atmosphere (the corona), an extended magnetic field filled with cool plasma forming a dark ribbon across the face of the sun (a feature known as a “filament”) erupted at the exact same time.

It seems very likely that both events were connected after a powerful shock wave produced by the flare destabilized the filament, causing the eruption.

A second solar observatory, the Solar and Heliospheric Observatory (SOHO), then spotted a huge coronal mass ejection (CME) blast into space, straight in the direction of Earth. Solar physicists have calculated that this magnetic bubble filled with energetic particles should hit Earth on August 3, so look out for some intense aurorae, a solar storm is on its way…

For more on this impressive solar eruption, read my Discovery News article, “Incoming! The Sun Unleashes CME at Earth