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Researchers working with Rosetta have found that the comet harbors organic compounds, carbon-based molecules that are sometimes known as the chemical building blocks of life. This marks the first time organic molecules have been detected on the surface of a comet's nucleus, according to Fabrizio Capaccioni, the principal investigator of the VIRTIS instrument on Rosetta. The northern hemisphere of the comet's nucleus is also filled with dunes and ripples that look somewhat like geological markings on Earth, Mars and Venus. Comet 67P/C-G doesn't have a robust atmosphere and high gravity like those planets, and yet it still has structures resembling...

NASA's Kepler Space Telescope, despite being hobbled by the loss of critical guidance systems, has discovered a star with three planets only slightly larger than Earth. The outermost planet orbits in the "Goldilocks" zone, a region where surface temperatures could be moderate enough for liquid water and perhaps life, to exist. The star, EPIC 201367065, is a cool red M-dwarf about half the size and mass of our own sun. At a distance of 150 light years, the star ranks among the top 10 nearest stars known to have transiting planets. The star's proximity means it's bright enough for astronomers...

Paris (AFP) - The Solar System has at least two more planets waiting to be discovered beyond the orbit of Pluto, Spanish and British astronomers say. The official list of planets in our star system runs to eight, with gas giant Neptune the outermost. Beyond Neptune, Pluto was relegated to the status of "dwarf planet" by the International Astronomical Union in 2006, although it is still championed by some as the most distant planet from the Sun. In a study published in the latest issue of the British journal Monthly Notices of the Royal Astronomical Society, researchers propose that "at...

Astronomers have discovered a potential "rogue" alien planet wandering alone just 100 light-years from Earth, suggesting that such starless worlds may be extremely common across the galaxy. The free-floating object, called CFBDSIR2149, is likely a gas giant planet four to seven times more massive than Jupiter, scientists say in a new study unveiled Wednesday. The planet cruises unbound through space relatively close to Earth (in astronomical terms), perhaps after being booted from its own solar system. "If this little object is a planet that has been ejected from its native system, it conjures up the striking image of orphaned worlds,...

Neptune's own existence was a puzzle until recently. The dusty cloud that gave birth to the planets probably thinned out further from the sun. With building material so scarce, it is hard to understand how Uranus and Neptune, the two outermost planets, managed to get so big. But what if they formed closer in? In 2005, a team of scientists proposed that the giant planets shifted positions in an early upheaval (New Scientist, 25 November 2006, p 40). In this scenario, Uranus and Neptune formed much closer to the sun and migrated outwards, possibly swapping places in the process. That...

CHICAGO (AFP) - Hundreds of rogue black holes may be roaming around the Milky Way waiting to engulf stars and planets that cross their path, US astronomers said Wednesday. The astronomers believe these "intermediate mass" black holes are invisible except in rare circumstances and have been spawned by mergers of black holes within globular clusters -- swarms of stars held together by their mutual gravity. These black holes are unlikely to pose a threat to Earth, but may engulf nebulae, stars and planets that stray into their paths, the researchers said. "These rogue black holes are extremely unlikely to do...

The Kepler space telescope has spotted over 1,000 exoplanets beyond our solar system, and its latest finds are three almost Earth-sized planets, including one in the habitable zone circling the star EPIC 201367075, just 150 light years from Earth. In the cosmic sense, that’s right around the block, making it one of the 10 closest known stars with observed planets in its gravitational hold. Of course, such distances in the cosmic sense also would take many generations to traverse, so don’t invest in real estate there just yet. Still, the relative closeness of this “EPIC” star and its planets provides...

Presently, our solar system is known to contain 4 fully-fledged rocky worlds: Mercury, Venus, Earth and Mars; 2 ice-giants: Neptune and Uranus; 2 gas-giants, Saturn and Neptune; 5 dwarf-planets, Ceres. Pluto, Eris, MakeMake, Haumea; around 100 moons; and an unknowable number of comets, asteroids and minor planets. Indeed, we’ve only begun to understand the full scope of our local corner of our galaxy, and new information emerges on a monthly-basis, yet there a number of seemingly obvious things that remain unknown. For instance, long before Pluto’s existence was deduced, astronomers scoured the outer solar system in search of another large...

In their studies, the team analyzed the effects of what is called the ‘Kozai mechanism,’ which is related to the gravitational perturbation that a large body exerts on the orbit of another much smaller and further away object. They looked at how the highly eccentric comet 96P/Machholz1 is influenced by Jupiter (it will come near the orbit of Mercury in 2017, but it travels as much as 6 AU at aphelion) and it may “provide the key to explain the puzzling clustering of orbits around argument of perihelion close to 0° recently found for the population of ETNOs,” the team...

A pulsar, one of deep space’s spinning “lighthouses”, has faded from view because a warp in space-time tilted its beams away from Earth. The tiny, heavy pulsar is locked in a fiercely tight orbit with another star. The gravity between them is so extreme that it is thought to emit waves and to bend space - making the pulsar wobble. By tracking its motion closely for five years, astronomers determined the pulsar’s weight and also quantified the gravitational disturbance. Then, the pulsar vanished. Its wheeling beams of radio waves now pass us by, and the researchers have calculated that this...

NASA's Mars Curiosity rover has measured a tenfold spike in methane, an organic chemical, in the atmosphere around it and detected other organic molecules in a rock-powder sample collected by the robotic laboratory's drill. "This temporary increase in methane -- sharply up and then back down -- tells us there must be some relatively localized source," said Sushil Atreya of the University of Michigan, Ann Arbor, a member of the Curiosity rover science team. "There are many possible sources, biological or non-biological, such as interaction of water and rock."

While asteroids residing in the inner solar system will pass quickly through such small fields, trans-Neptunian objects (TNOs) orbit the Sun much more slowly. For example, Pluto, at an approximate distance of 40 A.U. from the Sun, along with the object Eris, presently the largest of the TNOs, has an apparent motion of about 27 arc seconds per day – although for a half year, the Earth’s orbital motion slows and retrogrades Pluto’s apparent motion. The 27 arc seconds is approximately 1/60th the width of a full Moon. So, from one night to the next, TNOs can travel as much...

Stars Passing Close to the Sunby Paul Gilster on January 2, 2015 Every time I mention stellar distances I’m forced to remind myself that the cosmos is anything but static. Barnard’s Star, for instance, is roughly six light years away, a red dwarf that was the target of the original Daedalus starship designers back in the 1970s. But that distance is changing. If we were a species with a longer lifetime, we could wait about eight thousand years, at which time Barnard’s Star would close to less than four light years. No star shows a larger proper motion relative to...

Billions of years from now, when the earth has erased all traces of our stay here, hundreds of dead satellites will remain in orbit around the earth. Along with these pictures.

In fact, according to the authors of the new paper, there is a 90% chance that a GRB powerful enough to destroy Earth’s ozone layer occurred in our stellar neighborhood some time in the last 5 billion years, and a 50% chance that such an event occurred within the last half billion years. These odds indicate a possible trigger for the second worst mass extinction in Earth’s history: the Ordovician Extinction. This great decimation occurred 440-450 million years ago and led to the death of more than 80% of all species.

A New Physics Theory of Life Katherine Taylor for Quanta MagazineJeremy England, a 31-year-old physicist at MIT, thinks he has found the underlying physics driving the origin and evolution of life. By: Natalie WolchoverJanuary 22, 2014 Comments (151) print Why does life exist?Popular hypotheses credit a primordial soup, a bolt of lightning and a colossal stroke of luck. But if a provocative new theory is correct, luck may have little to do with it. Instead, according to the physicist proposing the idea, the origin and subsequent evolution of life follow from the fundamental laws of nature and “should be as...

A meteorite from Mars that landed on Earth in 2011 contains a carbon compound that is biological in origin. (snip) "We cannot and do not want to entirely exclude the possibility that organic carbon within Tissint may be of abiotic origin," Lin wrote, meaning the carbon maybe physical in origin rather than organic -- devoid of life.7 "It could be possible that the organic carbon originated from impacts of carbonaceous chondrite meteorites. However, it is not easy to conceive bywhich processes chondritic carbon could have been selectively extracted from the impacting carbonaceous chondrites, selectively removed from the soil and later...

Partial Ingredients For DNA And Protein Found Around Star NASA's Spitzer Space Telescope has discovered some of life's most basic ingredients in the dust swirling around a young star. The ingredients - gaseous precursors to DNA and protein - were detected in the star's terrestrial planet zone, a region where rocky planets such as Earth are thought to be born. The findings represent the first time that these gases, called acetylene and hydrogen cyanide, have been found in a terrestrial planet zone outside of our own. "This infant system might look a lot like ours did billions of years ago,...

We’ve heard it time and time again. When it comes to new exoplanet findings, our conventional wisdom never holds. So the surprise that a batch of extrasolar planets are moving retrograde, orbiting in directions opposite to the way their stars are spinning, shouldn’t come as a surprise. Then again, maybe it should. These discoveries turned the long-standing view of how planets form on its head. Now Eduard Vorobyov at the University of Vienna and colleagues argue that chaotic conditions in the planetary system’s gaseous wombs may be to blame. Theorists have long assumed that stars and their planetary companions assemble...

Inside a very big and very clean room at NASA’s Goddard Space Flight Center in Greenbelt, Md., nearly 30 workers dressed in white protective suits, goggles and blue booties cluster around the parts of a time machine. These parts — gold-covered mirrors, tennis-court-size sun shields, delicate infrared cameras — are slowly being put together to become the James Webb Space Telescope.