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Saturn Moon Has Oxygen Atmosphere

An oxygen atmosphere has been found on Saturn's second largest moon, Rhea, astronomers announced Thursday—but don't hold your breath for colonization opportunities. For one thing, the 932-mile-wide (1,500-kilometer-wide), ice-covered moon is more than 932 million miles (1.5 billion kilometers) from Earth. For another, the average surface temperature is -292 degrees Fahrenheit (-180 degrees Celsius). And at less than 62 miles (100 kilometers) thick, the newfound oxygen layer is so thin that, at Earthlike temperatures and pressure, Rhea's entire atmosphere would fit in a single midsize building. Still, the discovery implies that worlds with oxygen-filled air may not be so unusual in the cosmos. At about 327,000 miles (527,000 kilometers) from Saturn, Rhea orbits inside the planet's magnetic field. The Hubble Space Telescope and NASA's Galileo probe found in 1995 that a similar process creates tenuous oxygen atmospheres on Jupiter's ice moons Europa and Ganymede. Related:  space

Solar Breeze On August 25, 1997, NASA launched the Advanced Composition Explorer (ACE) satellite on a mission to monitor energetic ions coming from the Sun, as well as higher energy particles (cosmic rays) thought to be arriving from intergalactic space. ACE is in orbit around the L1 LaGrange point approximately 1,500,000 kilometers from Earth and will remain there until 2024. Scientists hope that data from the spacecraft's onboard sensors will help them understand how the Solar System formed, including how the solar magnetic field moderates incoming high-speed ions. Several research groups have been investigating a possible link between our climate and cosmic rays. During periods of high activity, energetic pulses on the Sun eject charged particles in the billions of tons. Although the Sun is in a relatively quiescent state with few sunspots visible, it occasionally erupts with solar flares that can reach incredible velocities. Sunlight reaches Earth in approximately eight minutes. Stephen Smith

Dark Jupiter May Haunt Edge of Solar System | Wired Science 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 could have a Jupiter-mass object out there.” In 1999, Matese and colleague Daniel Whitmire suggested the sun has a hidden companion that boots icy bodies from the Oort Cloud, a spherical haze of comets at the solar system’s fringes, into the inner solar system where we can see them. In a new analysis of observations dating back to 1898, Matese and Whitmire confirm their original idea: About 20 percent of the comets visible from Earth were sent by a dark, distant planet. “But we began to ask, what kind of an object could you hope to infer from the present data that we are seeing?” See Also:

Sights and Sounds of Titan Sights and Sounds of Titan The European Space Agency's Huygens probe has landed on Saturn's giant moon Titan. Listen to this story via streaming audio, a downloadable file, or get help. January 16, 2005: Congratulations, ESA! The European Space Agency's (ESA's) Huygens probe, carried to Saturn by the Cassini spacecraft, parachuted to the surface of Saturn's giant moon Titan on Friday, Jan. 14th, revealing finally what lies beneath Titan's thick orange clouds. Right: From an altitude of 16 km, Huygens photographed these drainage channels leading to a shoreline. First images released by the ESA depict sinuous drainage channels leading to an apparent shoreline. It's all a bit familiar, yet at the same time utterly alien. Above: Small "rocks," possibly made of water ice, at the Huygens landing site. Because Titan has a thick atmosphere, able to carry sound waves, the moon is a noisy place. Huygens was designed to float in case it landed in a river or lake--but it didn't.

BREAKING -- NASA Announces DISCOVERS BLACK HOLE ERUPTION! Milky Way 'bubbles' might be a black hole eruption Two mysterious `bubbles' have appeared in the galaxy, scientists claim it to be around 50,000 light years miles away. This distance is similar to that of exact distance halfway from the sun to the center of the Milky Way. Other elucidations claim that if the bubbles were seen by the naked eye they would go along halfway across the sky. The two gamma ray emitting bubbles go up to 25,000, light-years north and south of the galactic centre. Scientists seem to believe on two conclusions, either there is a presence of black hole amidst the center of the Milky Way- which is sized four million times the mass of the sun which releases energy burp sort of a thing, or, the bubbles were developed in a massive eruption of star formation in the Milky Way. Gamma-ray-emitting bubbles are yet studied upon as scientists seem to be unknown about their `nature' or `origin'. [link to] It IS A BLACKHOLE .... [link to] Or this?

Radiation Rings Hint Universe Was Recycled Over and Over | Wired Science Most cosmologists trace the birth of the universe to the Big Bang 13.7 billion years ago. But a new analysis of the relic radiation generated by that explosive event suggests the universe got its start eons earlier and has cycled through myriad episodes of birth and death, with the Big Bang merely the most recent in a series of starting guns. That startling notion, proposed by theoretical physicist Roger Penrose of the University of Oxford in England and Vahe Gurzadyan of the Yerevan Physics Institute and Yerevan State University in Armenia, goes against the standard theory of cosmology known as inflation. The researchers base their findings on circular patterns they discovered in the cosmic microwave background, the ubiquitous microwave glow left over from the Big Bang. The circular features are regions where tiny temperature variations in the otherwise uniform microwave background are smaller than average. See Also:

Enceladus Saturn II Enceladus ("en SEL a dus") is the eighth of Saturn's known satellites: orbit: 238,020 km from Saturn diameter: 498 km mass: 7.30e19 kg In Greek mythology Enceladus was a Titan who was defeated in battle and buried under Mount Etna by Athena. Discovered in 1789 by Herschel. Craters and smooth plains Enceladus has the highest albedo (>0.9) of any body in the solar system. At least five different types of terrain have been identified on Enceladus. This means that Enceladus must have been active until very recently (and perhaps is still active today). Enceladus is much too small to be heated solely by the decay of radioactive material in its interior at present. Cassini closeup view (looks like Europa?) Enceladus is locked in a 1:2 resonance with Dione (similar to the situation between Io and Europa). Enceladus is very likely the source of the material in Saturn's tenuous E ring. More about Enceladus Open Issues What is the resurfacing mechanism? Home ...

Hubble Ultra Deep Field 3D "Awesome" doesn't begin to describe this. It’s an uplifting and mind-expanding experience to have a glimpse of how the playground of the physical world extends outward farther than one had ever imagined. “We pointed the most powerful telescope ever built by human beings at absolutely nothing, just because we were curious, and discovered that we occupy a very tiny place in the heavens,” the narrator says. When the Hubble Telescope is pointed at an “empty” area of the sky, the images of over 10,000 galaxies appear in the telescope’s long-range view: Photons of these galaxies have traveled for 13 billion years to record their images for us to see. Also see Hubble Deep Field Each day the Flixxy team looks through hundreds of new videos to pull out a few we think are the best.

In Flyby of Saturn's Moon Rhea, Cassini Probe Gets First Whiff of Non-Earthly Oxygen NASA's Cassini spacecraft has taken a breath of oxygen while passing over the icy surface of Saturn's second-largest moon, marking the first time a spacecraft has directly sampled oxygen in the atmosphere of another body. Cruising just 60 miles above Rhea, one of more than 60 moons orbiting Saturn, Cassini found an extremely thin atmosphere of oxygen and carbon dioxide likely sustained by high-energy particles slamming into the moon's frozen surface. Rhea's isn't the only other atmosphere in the universe, but it is so thin that Cassini had to fly through it just to confirm that it was there at all (other atmosphere's have been detected and studied from afar by tools like the Hubble Space Telescope). According to Cassini's onboard science instruments, Rhea's atmosphere contains something like 50 billion oxygen molecules per cubic meter, matched by 20 billion carbon dioxide molecules. [Guardian]

The Unsolved Mystery of Saturn's Hexagon -4 Times the Size of Earth "Cassini is indebted to Voyager for its many fascinating discoveries and for pavingthe way for Cassini," says Linda Spilker, Cassini project scientist at JPL, who started her career working on Voyager from 1977 to 1989. "On Cassini, we still compare our data to Voyager's and proudly build on Voyager's heritage." But the Voyager Mission left a few mysteries that Cassini has not yet solved. One of the most perplexing mysteries is Saturn's hexagpn. 'Now that we can see undulations and circular features instead of blobs in the hexagon, we can start trying to solve some of the unanswered questions about one of the most bizarre things we've ever seen in the solar system, said Kevin Baines, Atmospheric scientist at NASA's Jet Propulsion Laboratory after viewing Cassini images in 2009. After the sunlight faded, darkness shrouded the north pole for 15 years. The hexagon was originally discovered in images taken by the Voyager spacecraft in the early 1980s.

Twinkling Stars May Reveal Human-Size Wormholes | Wired Science If wormholes big enough to fit a human or a spaceship exist, telescopes should be able to detect any wavering starlight the space-time shortcuts cause while moving in front of a distant star. Star brightness would fluctuate from a wormhole because of gravitational lensing, caused when a massive object (such as a galaxy) warps the fabric of space and bends light around it. The effect, which resembles the distortion of objects behind a thick lens, exaggerates with increasingly massive objects. When it comes to wormhole hunting, said Nagoya University astrophysicist Fumio Abe, looking for the distant signatures of smaller gravitational lenses, called microlenses, is the way to go. “Gravitational microlensing in stars has already been observed, but the variation of the brightness by a wormhole would be different from any ordinary star,” said Abe, whose wormhole-detecting methodology appears Dec. 10 in The Astrophysical Journal. “If they do turn out to exist, I’ll be ecstatic,” Visser said.

Super-Earth Atmosphere May Be Mostly Water | Wired Science The first direct measurement of a super-Earth exoplanet's atmosphere finds the world is either shrouded in steam or covered in clouds. "This is the first probe of an atmosphere of a super-Earth planet," said exoplanet observer Jacob Bean of the Harvard-Smithsonian Center for Astrophysics, lead author of a paper describing the cloudy world in the Dec. 2 Nature. "It's a real big step in the direction of doing this kind of work for a planet that's potentially habitable." The planet, called GJ 1214b, is the smallest planet yet to have its atmosphere examined -- but it's just the latest in nearly a decade of probing exoplanet atmospheres. When the first exoplanet atmosphere was measured in 2002, many astronomers dismissed it as a one-time success. Astronomers hope eventually to find true twins of Earth: small rocky planets with liquid water and atmospheres that could support life. "Ultimately the goal is to try to look for biosignatures," Bean said. Image: Paul A.