Supervolcanoes here on Earth capture a lot of attention; from doomsday predictions to TV specials to planetarium shows, many folks seem concerned about these phenomena occurring at any moment from far beneath our feet.

But when searching for volcanoes, instead of down, maybe we should look up. We have found many unusual types of volcanoes in space.

A recent photo of Io, one of Jupiter’s moons, has just revealed a massive eruption on the surface of the large moon. The spread of the returning material covers about 30 square kilometers (11.5 square miles), making it one of the largest eruptions humans have ever witnessed and placing it within the top ten eruptions on Io.

Why is Io so active? The most likely explanation is the gravitational tug of war between the tidally locked moon and the massive planet Jupiter. This constant pulling and stretching is keeping the moon warm and fluid.

But why do explosions halfway across the Solar System away interest scientists? What we learn about these volcanic eruptions can help us understand volcanoes here on Earth a bit better and also give us a glimpse “under the hood” of Io.

And perhaps the coolest reason of all? Scientists studying the ice moon next to Io, Europa, have found magnesium salts on the surface of that moon that may have been spread there by Io throwing material into orbit around Jupiter! Some of that volcanic spray may be shared amongst the rest of the great moons of Jupiter as well. Evidence that these worlds have a diverse mix of chemicals is a big step toward determining the kind of primordial soup that could exist upon (or within) them, not to mention the kind of chemistry—or, perhaps, even evolution—that could be occurring there.

Josh Roberts is a program presenter and astronomer at the California Academy of Sciences. He also contributes content to Morrison Planetarium productions.

Image: NASA’s Galileo spacecraft

Perhaps our solar system is rarer than we thought.

As astronomers search for exoplanets, the bigger, more massive planets prove easier to spot.  One of the easiest type of planets to find are hot Jupiters, planets similar in size to Jupiter that maintain a very close and fast orbit around their parent stars—even closer than Mercury orbits around our Sun! (For comparison, Jupiter orbits the Sun more than 20 times farther away than Mercury.) These big, hot planets have enough mass to exert a noticeable gravitational pull on their hosts.

There is more to these planets than meets the eye… Or perhaps less than meets the eye, according to a recent study published in the Proceedings of the National Academy of Sciences.

Typically, a hot Jupiter doesn’t have any companion planets—you might think of it as an only child compared to our family of eight planets orbiting the Sun. Astronomers theorize that many of these massive planets migrated from a large orbit to a smaller one. Their gravitational influence simply ejected other planets that got in their way. Even if a system started out with multiple planets, it might end up with only one.

Astronomers at the Fermilab Center for particle Astrophysics used data from NASA’s Kepler mission to look for transiting planets (we can see this in our own solar system on June 5th when Venus transits the Sun). The researchers analyzed 63 hot Jupiters, 31 warm Jupiters (which reside in slightly larger orbits around their parent stars), and 222 hot Neptunes (close to their parent stars, but not as hefty as hot Jupiters). The research team found no additional planets in any of the hot Jupiter systems, but on average, they found evidence for three possible companion planets around warm Jupiters, and two around hot Neptunes.

These results could imply that our home is unusual than other planetary systems. “The implications of these findings are that systems with Earth-like planets formed differently than systems with hot Jupiters,” says co-author Alan Boss. “Since we believe that hot Jupiters formed farther out, and then migrated inward toward their stars, the inward migration disrupted the formation of Earth-like planets. If our sun had a hot Jupiter, we would not be here.”

Alyssa Keimach is an astronomy and astrophysics student at the University of Michigan and volunteers for the Morrison Planetarium.

Image: NASA, ESA, and G. Bacon

Britney Schmidt, a postdoctoral fellow at the University of Texas at Austin, and her team were perusing data from the Galileo spacecraft. From 1995-2003, the Galileo mission studied Jupiter and some of its 64 moons, sending back a wealth of data that scientists are still studying today.

Several images of the icy moon Europa caught the team’s attention—especially those of roughly circular, bumpy features on its surface called chaos terrains. These chaos terrains looked familiar to the researchers, much like ice fields in Greenland and Antarctica here on Earth.

On our planet, these features correspond to ice shelves that sit on oceans or glaciers that cover volcanoes. The scientists wondered if the chaos terrains could be formed in similar ways and developed a model to test their theory.

Data from Galileo already suggested the existence of a saltwater ocean well below the surface of Europa—an ocean that contains more liquid water than all of Earth’s oceans combined! However, being so far from the Sun, the ocean surface is completely frozen. Most scientists think this ice crust is tens of miles thick.
“One opinion in the scientific community has been if the ice shell is thick, that’s bad for biology. That might mean the surface isn’t communicating with the underlying ocean,” said Schmidt at a NASA press conference yesterday.

But the bumpy surface could be good for biology. Schmidt’s model shows the chaos features on Europa’s surface may be formed by mechanisms that involve significant exchange between the icy shell and underlying lakes, equal in volume to North America’s Great Lakes.

These mechanisms could transfer nutrients and energy between the surface of the planet and the vast global ocean already inferred to exist below the thick ice shell. Which could increase the potential for life there.

“Now, we see evidence that it’s a thick ice shell that can mix vigorously and new evidence for giant shallow lakes. That could make Europa and its ocean more habitable,” reported Schmidt.

Still, because the lakes (if they exist) would lie a few miles below the surface, the only true confirmation of their presence would come from a future spacecraft mission designed to probe the ice shell.

So we’ll have to wait to confirm life on Europa, according to Wired.

Unfortunately, NASA does not currently have missions to explore Europa on its schedule… A proposed Jupiter-Europa Orbiter has an estimated price tag of $4.6 billion, making it unlikely to launch during a time of budget squeezes.

The research appears in the current edition of Nature.

Image: Britney Schmidt and Dead Pixel FX, University of Texas at Austin

Previous studies have noted that a “dynamical instability” (which is to say, a complex interaction of gravitational effects of different planets on one another) affected the orbits of giant planets when the solar system was a mere 600 million years old. As a result, the giant planets and smaller bodies scattered away from each other… A little bit of self-segregation.

Some small bodies migrated into the Kuiper Belt and others traveled farther inward, producing impacts on the terrestrial planets and the Moon. The giant planets shifted around as well. Jupiter, for example, scattered most small bodies outward and moved inward.

Jupiter played one of the biggest roles in the solar system’s youth. Scientists believe it protected smaller planets, like our own, from colliding with each other. Scientists explain the giant world’s protective status through the “jumping Jupiter” theory. “They proposed that Jupiter’s orbit quickly changed when Jupiter scattered off of Uranus or Neptune during the dynamical instability in the outer solar system,” says David Nesvorny of the Southwest Research Institute.

But when Nesvorny ran computer simulations of this “jumping Jupiter” theory, he ran into a problem. While Jupiter did in fact jump through interactions with Uranus or Neptune, the simulations also showed that Uranus or Neptune got knocked out of the solar system.

So Nesvorny wondered whether the early solar system could have had five giant planets instead of four. By running the simulations with an additional giant planet with mass similar to that of Uranus or Neptune, things suddenly fell in place.

Nesvorny believes that jumping Jupiter ejected one planet from the solar system, leaving the four gas giant planets we know and love behind. Thankfully, Jupiter jumped, leaving the terrestrial planets (including Earth) undisturbed.

“The possibility that the solar system had more than four giant planets initially, and ejected some, appears to be conceivable in view of the recent discovery of a large number of free-floating planets in interstellar space, indicating the planet ejection process could be a common occurrence,” says Nesvorny.

This research appears in a recent edition of the Astrophysical Journal Letters.

Image: Southwest Research Institute

A new analysis of data from NASA’s Galileo spacecraft reveals that beneath the surface of Jupiter’s volcanic moon Io is an “ocean” of molten or partially molten magma. The magma ocean layer appears to be more than 30 miles thick, making up at least 10 percent of the moon’s mantle by volume. The blistering temperature of the magma ocean probably exceeds 2,200 degrees Fahrenheit (1,200 degrees Celsius). Hotcha!

NASA’s Voyager spacecraft discovered Io’s volcanoes in 1979 and they are the only known active magma volcanoes in the solar system other than those on Earth. The energy for the volcanic activity comes from the squeezing and stretching of the moon by Jupiter’s gravity as Io orbits the immense planet, the largest in the solar system.

Even though the magnetic-field data was taken from Galileo fly-bys of Io in October 1999 and February 2000, it took awhile to detect this magma layer. ScienceInsider reports that

high-flying volcanic debris frustrated space physicists’ attempts to use Jupiter’s powerful magnetic field as a probe of Io’s interior.

The current analysis, over ten years in the making, was published in this week’s edition of Science.

From a hot ocean to hot Jupiters…  Hot Jupiters describe large gaseous exoplanets that orbit very close to their parent star. Some of these hot Jupiters are just plain crazy weird, say scientists, because they orbit their star in the opposite direction.

“That’s really weird, and it’s even weirder because the planet is so close to the star,” said Frederic A. Rasio, a theoretical astrophysicist at Northwestern University. “How can one be spinning one way and the other orbiting exactly the other way? It’s crazy. It so obviously violates our most basic picture of planet and star formation.”

When scientists find something weird and crazy, they investigate. And that’s just what Rasio and his colleagues did. Using large-scale computer simulations, they are the first to model how a hot Jupiter’s orbit can flip and go in the direction opposite to the star’s spin. Gravitational perturbations by a much more distant planet result in the hot Jupiter having both a “wrong way” and a very close orbit, according to their research, published this week in Nature.

In other exoplanet news… The Kepler mission’s primary goal is to find Earth-like planets orbiting Sun-like stars, and now you can help find them, too! UC Berkeley astronomers aimed a radio telescope in the direction of Kepler’s most Earth-like candidates last weekend. Once they acquire data on a total of 86 Earth-like planets, they’ll initiate a coarse analysis and then, in about two months, ask an estimated 1 million SETI@home users to conduct a more detailed analysis on their home computers. Join SETI@home or learn more information about the project here.

Io image: NASA/JPL/University of Michigan/UCLA

The scientists used data from NASA’s Cassini, Galileo and New Horizons missions (dating from 1996 to 2009) to search the ring systems of Jupiter and Saturn for patterns of cometary disruptions.

In the case of Jupiter, the ripple-producing culprit was the well-known comet Shoemaker-Levy 9, whose debris cloud hurtled through the thin Jupiter ring system during a kamikaze course into the planet in July 1994. Scientists attribute Saturn’s ripples to a similar object—likely another cloud of comet debris—plunging through the inner rings in the second half of 1983. The researchers believe this comet passed through when Saturn was on the other side of the Sun from Earth.

“We now know that collisions into the rings are very common—a few times per decade for Jupiter and a few times per century for Saturn,” said Mark Showalter of SETI and lead author of the paper on Jupiter. “Now scientists know that the rings record these impacts like grooves in a vinyl record, and we can play back their history later.”

The tightness of the rings’ “grooves” gives clues to when the comet debris came hurling through, according to Nature News:

As time passed, this tilt has become a progressively tighter spiral, meaning that the shorter the ripple’s wavelength, the longer ago it was formed.

(Discover has a great NASA video of the rings becoming tighter with age on their site.)

The ripples also give scientists a measurement of the size of the clouds of cometary debris that hit the rings. In each of these cases, the nuclei of the comets were a few kilometers wide before they likely broke apart.

“Finding these fingerprints still in the rings is amazing and helps us better understand impact processes in our solar system,” said Linda Spilker, Cassini project scientist, based at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “Cassini’s long sojourn around Saturn has helped us tease out subtle clues that tell us about the history of our origins.”

“What’s cool is we’re finding evidence that a planet’s rings can be affected by specific, traceable events that happened in the last 30 years, rather than a hundred million years ago,” said Matthew Hedman, of Cornell and lead author of the Saturn paper. “The solar system is a much more dynamic place than we gave it credit for.”

Image credit: NASA/JPL-Caltech/SETI

Earth

The Gulf oil spill—the number of gallons spilled and the controversy surrounding the damage seems to top many lists this year. Nature even named Jane Lubchenco, head of NOAA, its newsmaker of the year for how she handled the crisis.

Natural disasters often took the front page in 2010 with the Haitian earthquake and the eruption of Eyjafjallajökull topping many lists. The hard-to-pronounce Icelandic volcano also made many of the best science images of the year lists.

DiscoveryNews ends the year on a positive note with “How Humans Helped the Earth in 2010,” a slide show with text concerning recent strides in alternative energy, species and habitat conservation efforts and individual efforts to go green (electric cars, white roofs and saving energy).

For more environmental news of the year, New Scientist’s Short Sharp Science has a great review and the Nature Conservancy has a best/worst list on its site.

Life

Teeny, modified life stole the spotlight this year—the J. Craig Venter Institute’s so-called “synthetic cell” and GFAJ-1—the bacteria that incorporates arsenic into its DNA—or so NASA scientists claimed.  Science writer Carl Zimmer discredited the arsenic bacteria paper on Slate; NASA author Felisa Wolfe-Simon defended herself in Science. Fun stuff!

The spread of pesky bedbugs was number six in Discover’s “Top 100 Science Stories of 2010.”

Nature’s great article this past summer on eradicating mosquitoes was among its readers’ top choices of the year.

Looking for something a little bigger and less controversial? New Scientist has “The coolest animals of 2010,” which includes a scorpion-eating bat and a fly thought to be extinct for over 160 years!

NPR found it was a very good year for Neanderthals—their genome was sequenced, brain examined and diet expanded.

Remarkably, the Census of Marine Life tops the BP oil spill in the Deep Type Flow blog’s biggest marine science stories of the year for its sheer numbers:

…over 500 research expeditions covering every ocean, over 2,500 scientists and the discovery of over 6,000 species new to science and published in over 2600 peer-reviewed papers.

Space

ScienceNow’s most popular story of all time, not just 2010, was “Does Our Universe Live Inside a Wormhole?” A wonderful theory that we also covered last spring.

Exoplanets, in part thanks to the Kepler mission, were all over the news this year—whether it had to do with size, atmosphere or number within a star system. Discover’s interview with local exoplanet hunter (and California Academy of Sciences Fellow) Geoff Marcy made number 11(!) on their 100 top stories list.

A little closer to home, Jupiter’s missing stripe and Neptune’s tale of cannibalism are included in New Scientist’s most popular space stories of 2010.

Our Moon and Saturn’s moons made news throughout the year and the top lists on Universe Today and Wired this week.

Universe Today also included SDO’s new views of the sun in their top stories list. Stunning!

Hubble celebrated its 20^th year in space this year by taking even more beautiful images. Several are included in Bad Astronomy’s “Top 14 Astronomy Pictures of 2010.”

Technology

Electric cars and NASA’s new foray into commercial spacecraft are included in Scientific American’s top ten stories of the year.

The Large Hadron Collider was very busy this year, and topped many lists. Another machine at CERN made news (and also topped Nature’s readers’ choice list) when it was able to capture antimatter for a sixth of a second!

Graphene not only garnered a Nobel Prize this year, the material (and it’s potential) also made news and top science lists of the year.

DiscoveryNews put plastics on their 2010 list—whether its finding new ways of removing plastic from the oceans or engineering smarter plastics.

What was your favorite science story of the year? Share with us by adding it to the comment section below!

Image by Les Stone, International Bird Rescue Research Center/Wikipedia

What happened to the belt?  Will it return?

The belt is a globe-girdling band of sinking, chemically-stained gases resulting from convective processes in Jupiter’s atmosphere, and it is known to have vanished on previous occasions – most recently in 1973 and again in the early 1990s – but astronomers weren’t been able to explain why.  The current thinking is that a short-lived, high-altitude haze of ammonia ice crystals has hidden the darker cloud belt below and should start dissipating in a few months.  Already, the presence of a chain of dark spots along the southern edge of the Southern Equatorial Belt’s location is said to indicate an imminent change.   Keep watching Jupiter – currently visible in the predawn sky – to see the changes occurring in real-time in the atmosphere of the giant planet!

Though it has benefited greatly from the power of online connectivity, citizen science is not a new concept, it’s not all astronomical in nature, and it doesn’t necessarily require a computer.

The oldest citizen science project is the Christmas Bird Count, a census of birds of the Western Hemisphere that was started by the Audubon Society in 1900.  One of the newest is the campaign to monitor the eclipsing binary star system Epsilon Aurigae, where every 27 years one component of the star system blocks the other from view for about 2 years.

In 2007, the Citizen Science Alliance launched an online project called Galaxy Zoo, inviting guests to log in and classify distant galaxies by their shapes—spiral, barred spiral, edge-on, or irregular.  An instant hit, Galaxy Zoo became enormously popular and opened the door for additional projects that included observations of merging galaxies, searches for solar flares and supernovae, and, most recently, classification of features on the Moon, all under the broad project name “Zooniverse”.

Zooniverse follows in the footsteps of one of the best-known online popular science projects, SETI@home, based at the University of California’s Space Sciences Lab and which was launched in 1999.  A more passive approach, SETI@home uses the idle-time on subscribers’ computers to activate a screensaver that doubles as a signal analyzer. The analyzer searches downloaded packages of signal data detected by radio telescopes for patterns that might indicate intelligent activity.

Citizen scientists have much to offer to real science. It was almost a year ago that amateur astronomer Anthony Wesley discovered a new spot on Jupiter that had scientists pointing their telescopes in a new direction. Today, Hubble announced the cause of the spot: an asteroid.