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A Black Hole´s Dinner

June 26, 2012 Leave a comment

A giant gas cloud is on collision course with the black hole in the centre of our galaxy in 2013. This is a unique opportunity to observe how a super massive black hole sucks in material, in real time.The black hole at the centre of the galaxy, formally known as Sagittarius A*, fascinates scientists. By mid-2013 a gas cloud is expected to pass in its vicinity at a distance of only 36 light-hours (equivalent to 40.000.000.000km), which is extremely close in astronomical terms.For the past 20 years, Stefan Gillessen, astrophysicist at the Max Planck Institute for Extraterrestrial Physics in Munich, Germany, has been observing the black hole. “So far there were only two stars that came that close to Sagittarius A*”, he says. “They passed unharmed, but this time will be different: the gas cloud will be completely ripped apart by the tidal forces of the black hole.”  A black hole is what remains after a super massive star dies. When the “fuel” of a star runs low, it will first swell and then collapse to a dense core. If this remnant core has more than three times the mass of our Sun, it will transform to a black hole.

Direct observations of such black holes are impossible because they are coal-black and do not emit light or matter. But astronomers can identify a black hole indirectly due to the gravitational forces observed in their vicinity.

So-called super massive black holes are the largest type of black holes. Their mass equals hundreds of thousands to a billion times the mass of our sun. The centre of all galaxies is thought to contain super massive black holes. But their origin is not fully understood and astrophysicists can only speculate as to what happens inside them. Hence the imminent collision is of great interest to scientists as it should provide some new insights.

Full Story: http://www.youris.com/Environment/Space/A_Black_HoleS_Dinner.kl

NASA’s Hubble Spots Rare Gravitational Arc from Distant, Hefty Galaxy Cluster

June 26, 2012 Leave a comment

Seeing is believing, except when you don’t believe what you see. Astronomers using NASA’s Hubble Space Telescope have found a puzzling  arc of light behind an extremely massive cluster of galaxies residing  10 billion light-years away. The galactic grouping, discovered by NASA’s  Spitzer Space Telescope, was observed when the universe was roughly a  quarter of its current age of 13.7 billion years.

The giant arc is the stretched shape of a more distant galaxy whose  light is distorted by the monster cluster’s powerful gravity, an effect  called gravitational lensing. The trouble is, the arc shouldn’t exist.

Full Story: http://hubblesite.org/newscenter/archive/releases/2012/19/

Houston Workshop Marks Key Step in Planning Future Mars Missions

June 26, 2012 Leave a comment

A recent workshop conducted for NASA by the Lunar and Planetary Institute (LPI) in Houston, marked a key step in the agency’s effort to forge a new Mars strategy in the coming decades. A report that summarizes the wide range of cutting-edge science, technology and mission concepts discussed is available online [see below].
Held in Houston June 12-14 and attended by scientists and engineers worldwide, the meeting was held to seek ideas, concepts and capabilities to address critical challenge areas in exploring the Red Planet. Discussions provided information for reformulating NASA’s Mars Exploration Program (MEP) to be responsive to high-priority science goals and the challenge of sending humans to Mars orbit in the 2030s.
Participants identified a number of possible approaches to missions that can be flown to Mars in the coming decade that would make progress toward returning Martian samples — a top priority of the Planetary Science Decadal Survey — and make significant advances in scientific understanding of the planet, developing key technologies and advancing knowledge necessary for human exploration on and around Mars.

Full Story: http://www.nasa.gov/home/hqnews/2012/jun/HQ_12-215_Mars_LPI_Summary_Report.html

Astronomers Spot Rare Arc From Hefty Galaxy Cluster

June 26, 2012 Leave a comment

Seeing is believing, except when you don’t believe what you see. Astronomers using NASA’s Hubble Space Telescope have found a puzzling arc of light behind an extremely massive cluster of galaxies residing 10 billion light-years away. The galactic grouping, discovered by NASA’s Spitzer Space Telescope, was observed as it existed when the universe was roughly a quarter of its current age of 13.7 billion years.
The giant arc is the stretched shape of a more distant galaxy whose light is distorted by the monster cluster’s powerful gravity, an effect called gravitational lensing. The trouble is, the arc shouldn’t exist.
“When I first saw it, I kept staring at it, thinking it would go away,” said study leader Anthony Gonzalez of the University of Florida in Gainesville, whose team includes researchers from NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “According to a statistical analysis, arcs should be extremely rare at that distance. At that early epoch, the expectation is that there are not enough galaxies behind the cluster bright enough to be seen, even if they were ‘lensed,’ or distorted by the cluster. The other problem is that galaxy clusters become less massive the further back in time you go. So it’s more difficult to find a cluster with enough mass to be a good lens for gravitationally bending the light from a distant galaxy.”
Galaxy clusters are collections of hundreds to thousands of galaxies bound together by gravity. They are the most massive structures in our universe. Astronomers frequently study galaxy clusters to look for faraway, magnified galaxies behind them that would otherwise be too dim to see with telescopes. Many such gravitationally lensed galaxies have been found behind galaxy clusters closer to Earth.

Full Story: http://www.jpl.nasa.gov/news/news.cfm?release=2012-187

Thruster Tests Complete for NASA Partner Boeing’s Crew Capsule

June 26, 2012 Leave a comment

Pratt and Whitney Rocketdyne has successfully completed a series of tests on a thruster destined for Boeing’s Commercial Space Transportation spacecraft, designated CST-100.Boeing is one of several companies working to develop crew transportation capabilities under the Commercial Crew Development Round 2 agreement with NASA’s Commercial Crew Program. The goal of the program is to help spur innovation and development of safe, reliable and cost-effective spacecraft and launch vehicles capable of transporting astronauts to low Earth orbit and the International Space Station.
Twenty-four thrusters will be part of the spacecraft’s orbital maneuvering and attitude control system (OMAC), giving the CST-100 the ability to maneuver in space and during re-entry. The thrusters also will allow the spacecraft to separate from its launch vehicle if an abort becomes necessary during launch or ascent.
“Boeing and Pratt and Whitney Rocketdyne know what it takes to develop safe systems and subsystems,” said NASA Commercial Crew Program Manager Ed Mango. “They’re building on the successes of their past, while pushing the envelope with next-generation ideas to create a spacecraft for low Earth orbit transportation.”
During tests conducted at the White Sands Space Harbor in Las Cruces, N.M., an OMAC thruster was fired in a vacuum chamber that simulated a space-like environment of 100,000 feet. The tests verified the durability of the thrusters in extreme heat, evaluated the opening and closing of its valves and confirmed continuous combustion and performance.

Full Story: http://www.nasa.gov/home/hqnews/2012/jun/HQ_12-214_Boeing_PWR_OMAC_Test.html

NASA Hosts First Multi-Center Social Media Event for Mars Landing

June 26, 2012 Leave a comment

NASA is inviting its social media followers to the first ever multi-center NASA Social on Aug. 3, 2012, to preview the landing of the Mars Science Laboratory’s Curiosity rover on Aug. 5 PDT. NASA Socials are in-person meetings with people who engage with the agency through Twitter, Facebook, Google+ and other social networks.
Events will be held simultaneously at six NASA field centers, including Ames Research Center in Moffett Field, Calif.; Glenn Research Center in Cleveland; Goddard Space Flight Center in Greenbelt, Md.; Johnson Space Center in Houston; and, Langley Research Center in Hampton, Va. Each center will be connected via a multi-center NASA Television simulcast with NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif., during its NASA Social, which was previously announced. JPL, a division of the California Institute of Technology, Pasadena, manages the Mars Science Laboratory (MSL) mission for NASA.Participants will learn about the Mars Science Laboratory mission and their respective NASA field center host. They are encouraged to share their experience with others through their favorite social networks. Along with discussing MSL and Mars, participants will get a unique behind-the-scenes look at the center and the diverse work of the agency through tours and presentations by scientists, engineers and managers. The events also will provide guests the opportunity to interact with fellow social media users, space enthusiasts and members of NASA’s social media team.

Full Story:  http://www.nasa.gov/centers/ames/news/releases/2012/12-47AR.html

Cassini Shows Why Jet Streams Cross-Cut Saturn

June 26, 2012 Leave a comment

Turbulent jet streams, regions where winds blow faster than in other places, churn east and west across Saturn. Scientists have been trying to understand for years the mechanism that drives these wavy structures in Saturn’s atmosphere and the source from which the jets derive their energy.
In a new study appearing in the June edition of the journal Icarus, scientists used images collected over several years by NASA’s Cassini spacecraft to discover that the heat from within the planet powers the jet streams. Condensation of water from Saturn’s internal heating led to temperature differences in the atmosphere. The temperature differences created eddies, or disturbances that move air back and forth at the same latitude, and those eddies, in turn, accelerated the jet streams like rotating gears driving a conveyor belt.
A competing theory had assumed that the energy for the temperature differences came from the Sun. That is how it works in the Earth’s atmosphere.
“We know the atmospheres of planets such as Saturn and Jupiter can get their energy from only two places: the Sun or the internal heating. The challenge has been coming up with ways to use the data so that we can tell the difference,” said Tony Del Genio of NASA’s Goddard Institute for Space Studies, N.Y., the lead author of the paper and a member of the Cassini imaging team.

Full Story: http://www.jpl.nasa.gov/news/news.cfm?release=2012-186