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Scientists Now Know: We're From Sagittarius Dwarf Galaxy!

Scientists Now Know: We're Not From Here! Summary & comments by Dan Eden for Viewzone "This first full-sky map of Sagittarius shows its extensive interaction with the Milky Way," Majewski said. "Both stars and star clusters now in the outer parts of the Milky Way have been 'stolen' from Sagittarius as the gravitational forces of the Milky Way nibbled away at its dwarf companion. This one vivid example shows that the Milky Way grows by eating its smaller neighbors." The study's map of M giants depicts 2 billion years of Sagittarius stripping by the Milky Way, and suggests that Sagittarius has reached a critical phase in what had been a slow dance of death. "After slow, continuous gnawing by the Milky Way, Sagittarius has been whittled down to the point that it cannot hold itself together much longer," said 2MASS Science Team member and study co-author Martin Weinberg of the University of Massachusetts. Does this mean we are at a unique moment in the life of our galaxy? From Dan Eden: Hi Dan,

Quark Star (update) Some of the strange stuff that is coming out about quark stars: 1) that quark stars may be connected to dark matter (or even dark energy?) Some dark matter might just be “strangelets” roaming the cosmos, blasted free from quark stars: or 2) That some smaller sized black holes may actually be quark stars: “Some black holes may actually be ‘quark stars’:” or 3) The light given off by a quark star is called bremsstrahlung emissions. “quark star: gives off dim light (called bremsstrahlung emission), emitted by a thin layer of electrons on its surface:” or 4) It takes about 1.6 minutes to from a quark star from a neutron star. Like this: Like Loading...

The Fermi Gamma-ray Space Telescope Dark alien planet discovered by NASA | MNN - Mother Nature Network - StumbleUpon An alien world blacker than coal, the darkest planet known, has been discovered in the galaxy. The world in question is a giant the size of Jupiter known as TrES-2b. NASA's Kepler spacecraft detected it lurking around the yellow sun-like star GSC 03549-02811 some 750 lightyears away in the direction of the constellation Draco. The researchers found this gas giant reflects less than 1 percent of the sunlight falling on it, making it darker than any planet or moon seen up to now. "It's just ridiculous how dark this planet is, how alien it is compared to anything we have in our solar system," study lead-author David Kipping, an astronomer at the Harvard-Smithsonian Center for Astrophysics, told "However, it's not completely pitch black," co-author David Spiegel of Princeton University said in a statement. "It's a mystery as to what's causing it to be so dark," Kipping said. These extremely small fluctuations in light proved that TrES-2b is incredibly dark. Related on

Darkest exoplanet spotted by astronomers 12 August 2011Last updated at 11:09 By Jason Palmer Science and technology reporter, BBC News TrES-2b is literally darker, on average, than coal A dark alien world, blacker than coal, has been spotted by astronomers. The Jupiter-sized planet is orbiting its star at a distance of just five million km, and is likely to be at a temperature of some 1200C. The planet may be too hot to support reflective clouds like those we see in our own Solar System, but even that would not explain why it is so dark. The research will be published in the journal Monthly Notices of the Royal Astronomical Society. The planet, called TrES-2b, is so named because it was first spotted by the Trans-Atlantic Exoplanet Survey in 2006. It also lies in the field of view of the Kepler space telescope, whose primary mission is to spot exoplanets using extremely sensitive brightness measurements as far-flung worlds pass in front of their host stars. 'Exotic chemistry' Continue reading the main story

The Sounds of Pulsars A pulsar is a highly magnetised neutron star, with a radius of 10-15 km, having somewhat greater mass than the Sun which has a radius of approximately 1 million km. Radiation is beamed out along the magnetic poles and pulses of radiation are received as the beam crosses the Earth, in the same manner as the beam from a lighthouse causes flashes. Being enormous cosmic flywheels with a tick attached, they make some of the best clocks known to mankind. These sounds directly correspond to the radio-waves emitted by the brightest pulsars in the sky as received by some of the largest radio telescopes in the world.

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. NASA scientists first spotted a hexagonal weather pattern when they stitched together Voyager images of Saturn's north pole. '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.

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.

The James Webb Space Telescope