The search for life in the solar system, whether in rocks from Mars or on a Jovian moon, tops the wish list of a panel of space scientists convened by the National Research Council. Mindful of shrinking budgets, the panel has issued hard-nosed recommendations that identify which planetary science missions NASA should fly in the decade beginning 2013. Even some top-rated missions should be either deferred... 

The confirmed origin of ordinary cosmic rays may need to be unconfirmed. New data gathered by an instrument onboard a Russian spacecraft challenge the theory that most cosmic rays are fueled by supernovas, the explosions created by dying stars. “The mechanism for the acceleration of cosmic rays needs to be completely revised,” says Piergiorgio Picozza, a physicist at the University of Rome Tor... 

Two companies promising routine suborbital access have signed the first-ever contracts to ferry researchers beyond the Earth’s limb and into space. Virgin Galactic, a suborbital spaceflight company that’s building a spaceport in New Mexico, will fly at least two Southwest Research Institute researchers and their experiments into space at a cost of $200,000 per person. The institution has also... 

The ultra-dense meains of the galaxy’s youngest supernova are full of bizarre quantum matter. Two new studies show for the first time that the core of the neutron star Cassiopeia A, is a superfluid, a friction-free state of matter that normally only exists in ultra-cold laboratory settings. “The interior of neutron stars is one of the best kept secrets of the universe,” said astrophysicist Dany... 

NASA will launch a new satellite designed to probe how the sun and the Earth’s atmosphere conspire to shape Earth’s climate early Friday morning. The satellite, called Glory, will watch the sun and the Earth’s atmosphere simultaneously to see how they interact. The six-foot-tall satellite comes equipped with instruments to measure the amount of solar energy that strikes the top of the atmosphere,... 

When a couple dozen companies sign contracts containing the words “moon” and “landing,” it’s a good indication that private lunar exploration is heating up. The X Prize Foundation on Thursday announced that 29 teams had signed contracts making them the official Google Lunar X Prize competitors, contending for more than $30 million in prizes. The competitors, headquartered in 17 different... 

15 years after NASA astronomer David Williams started searching for them, hundreds of trees grown from space-faring seeds are still missing. The “moon trees,” whose seeds circled the moon 34 times in Apollo 14 astronaut Stuart Roosa’s pocket, were welcomed back to Earth with great fanfare in 1971. One was planted in Washington Square in Philadelphia as part of the 1975 bicentennial celebrations.... 

Before trying to contact aliens, maybe we should test the messages on ourselves. In a new paper in the journal Space Policy, three alien hunters suggest designing a standard protocol for writing intelligible letters to extraterrestrials, and building a website where teams can decode candidate messages to ensure they make sense. “The basic idea is, if you’re going to talk to aliens, you’d better... 

After a month and a half trapped in its mothership, NASA’s NanoSail-D spacecraft has finally unfurled the first solar sail to circle the Earth. Solar sails, gossamer-thin sheets that feel the pressure of the solar wind, have been suggested as a best hope for propelling spacecraft between the stars. They’re the only known method of space travel that doesn’t require carrying heavy fuel on the... 

SEATTLE — This gorgeous new X-ray image of the nearby galaxy M82 shows a frantic burst of star formation that may have been triggered by a close encounter with a nearby galaxy. M82 is “the prototypical starburst galaxy in the nearby universe,” said astronomer Roy Kilgard of Wesleyan University, who presented the new image in a press conference Thursday at the meeting of the American Astronomical... 

An enormous storm has erupted in Saturn’s northern hemisphere. Amateurs first sighted the storm earlier this month, but the Cassini spacecraft moved into a good position on Dec. 24 to photograph it from about 1.1 million miles away. Earth received the raw and unprocessed shots today. The storm has a huge central funnel and a long tail that sweeps around Saturn’s northern hemisphere for tens of... 

A century of comet data suggests a dark, Jupiter-sized object is lurking at the solar system’s outer edge and hurling chunks of ice and dust toward Earth. “We’ve accumulated 10 years’ more data, double the comets we viewed to test this hypothesis,” said planetary scientist John Matese of the University of Louisiana at Lafayette. “Only now should we be able to falsify or verify that you... 

New Hubble images reveal what happened to one of Jupiter’s main cloud belts: It’s hiding behind ammonia clouds. “Weather forecast for Jupiter’s Southern Equatorial Belt: cloudy with a chance of ammonia,” planetary scientist Heidi Hammel of the Space Science Institute in Boulder, Colorado said in a press release Wednesday. The gas giant’s characteristic band of dark clouds started fading... 

The Cassini spacecraft made its deepest dip ever into the atmosphere of Titan, Saturn’s largest moon, at 8:28 p.m. Eastern time on June 20. The data it collected will help determine whether the moon has its own magnetic field. “For Titan scientists, this is one of the most anticipated flybys of the whole mission,” wrote space physicist Cesar Bertucci of the Institute of Astronomy and Space Physics... 

Giant planets with wonky orbits mostly circle blistering-hot stars, two new studies find. This pattern could explain why some “hot Jupiters” — planets from a third to 12 times the mass of Jupiter that sit scorchingly close to their stars — orbit the way their star spins, while others tilt so far that they orbit backward. “It’s a possible resolution of what would otherwise be a weird fluke,”... 

Wear patterns on ancient antelope teeth have allowed researchers to reconstruct Europe’s environment 8 million years ago, when the continent’s great apes vanished. One of those ape species could have given rise to the human lineage, making the circumstances of their disappearance especially interesting. “Some kind of homogeneity happened around that time,” said anthropologist Gildas Merceron... 

A thick haze of organic material let the early Earth soak up the sun’s warmth without absorbing harmful ultraviolet rays, according to a new study. The model offers a new twist on an old puzzle: Although the sun was so dim billions of years ago that the Earth should have been a ball of ice, the young planet had liquid oceans capable of supporting life. “Given these recent papers, we can probably... 

The flashes of white light accompanying some solar flares are caused by the sun’s acceleration of electrons to speeds greater than half the speed of light. The phenomenon’s new explanation derives from data recorded from a 2006 solar flare. The presence of high-energy X-rays in the same spot that scientists saw visible light tipped them off that some kind of non-thermal process was generating... 

Exoplanet orbits that seem just right for life could be bent out of shape by pushy neighbors. New simulations of extrasolar planetary systems may mean the definition of “habitable” planets needs to be completely overhauled. When astronomers talk about the “habitable zone,” they mean the shell around a star where the temperatures are right for liquid water. Any closer, and oceans will boil.... 

Detailed Hubble images reveal a single supermassive black hole wandering away from its host galaxy’s center where it belongs. The misplaced black hole is probably the result of a merger between two smaller black holes, but could also have been pushed by a jet of matter extending from the galaxy’s core. Nearly every galaxy has a supermassive black hole — millions to billions of times more massive...