Are Stellar Explosions Created Equal?

ScienceDaily (2011-08-23) -- A new analysis of Type Ia supernova, used to measure cosmic distance, suggests many of them develop from similar initial conditions.

"Highly important among such clues are supernovae, extremely luminous stellar explosions. The distance to a supernova of a particular type, called Type Ia, can be calculated from its brightness: the brighter it appears, the closer it is to the viewer. Thanks to such supernovae, for example, astronomers have famously revealed that our universe is expanding at an accelerated pace, which suggests that it's permeated with mysterious dark energy. These calculations, however, are based on the assumption that all Type Ia supernovae have the same luminosity. Are all these explosions indeed created equal?"


Darkest Known Exoplanet: Alien World Is Blacker Than Coal

"Astronomers have discovered the darkest known exoplanet -- a distant, Jupiter-sized gas giant known as TrES-2b. Their measurements show that TrES-2b reflects less than one percent of the sunlight falling on it, making it blacker than coal or any planet or moon in our solar system."


NASA's Mars Rover Opportunity has reached its next destination.

"Three years after climbing out of Victoria crater, Opportunity has completed an eleven-mile trek to the rim of Endeavour crater at a spot informally named "Spirit Point" after the rover's decommissioned twin.
At 14 miles in diameter, Endeavour is an inviting work site for Opportunity. Orbital observations indicate that the ridges along its western rim expose rock outcrops older than any Opportunity has seen so far."



The Milky Way's Supermassive Black Hole


The Milky Way's supermassive black hole

Supermassive black holes - objects with masses of millions or even billions of suns - are found at the nuclei of galaxies. Our Milky Way galaxy, for example, has a massive black hole at its core, albeit one that is relatively quiescent. Despite their reputation for being implacable sinks for matter and energy, both radiation and matter can be ejected from the vicinity of a black hole, often in powerful jets, when it is ringed by a disk of matter and material accretes onto it.



NASA's Juno Mission to Jupiter is Solar Powered

"NASA's Juno spacecraft is heading for Jupiter this week with a novel energy source for a deep space probe — solar power — making it the farthest robotic space traveler to run on sunlight, scientists say."


Molecular Oxygen, O2, Found in Space

"For the first time, astronomers have found molecular oxygen, which makes up about 20 percent of our air on Earth, in space. Using the large telescope aboard the Herschel Space Observatory, a team of researchers from the European Space Agency and NASA detected the simple molecule in a star-forming region of the  Orion Nebula, located about 1,500 light-years from Earth. This takes astronomers one step closer to discovering where all of the oxygen in space is hiding."


Shadowy Galaxy Has Most Dark Matter Than Any Other Known Galaxy

"Astronomers have discovered a galaxy harboring more dark matter than any seen before."

"The galaxy is a small group of about 1,000 small, dim stars just outside the Milky Way called Segue 1. But while most of those stars appear to have roughly the mass of the sun, the galaxy as a whole weighs 600,000 times the mass of the sun. That means the normal matter stars are vastly outweighed by dark matter."


Space Probe Dawn is Investigating the Asteroid Vesta

"The giant asteroid Vesta is revealing more of itself to the US space agency's (NASA) Dawn mission. The probe has beamed back further images since entering into orbit around the 530km-wide rock on 17 July."