New Study Finds Clumps and Streams of Dark Matter in the Milky Way
Written by Nancy Atkinson



One of the leading theories for how the universe evolved after the Big Bang is the Cold Dark Matter Theory (CDM). This theory proposes that chilly dark matter moved slowly in the early universe, allowing matter to clump together to form the clusters of galaxies that we see, instead of matter being distributed evenly across the universe. Using the properties of the CDM theory, astronomers recently ran an intensive computer program using one of the world's most powerful supercomputers to simulate the halo of dark matter that envelopes our galaxy. The simulation revealed dense clumps and streams of the mysterious dark matter lurking within our Milky Way galaxy, including the region of our solar system.

"In previous simulations, this region came out smooth, but now we have enough detail to see clumps of dark matter," said Piero Madau, professor of astronomy and astrophysics at the University of California, Santa Cruz.

This simulation, detailed in an article in the journal Nature, may help may help scientists figure out what dark matter actually is. So far, it has been detected only through its gravitational effects on stars and galaxies. Another part of the CDM theory says that dark matter consists of weakly interacting massive particles (WIMPs), which can annihilate each other and emit gamma rays when they collide. Gamma rays from dark matter annihilation could be detected by the recently launched Gamma-ray Large Area Space Telescope (GLAST).

"That's what makes this exciting," Madau said. "Some of those clumps are so dense they will emit a lot of gamma rays if there is dark matter annihilation, and it might easily be detected by GLAST."

If so, it would be the first direct detection of WIMPS.

Although the nature of dark matter remains a mystery, it appears to account for about 82 percent of the matter in the universe. The clumps of dark matter created "gravitational well" that draws in ordinary matter, giving rise to galaxies in the centers of dark matter halos.

Using the Jaguar supercomputer at Oak Ridge National Laboratory, the simulation took about one month to run and simulated the distribution of dark matter from for 13.7 billion years – from near the time of the Big Bang until the current epoch. Running on up to 3,000 processors in parallel, the computations used about 1.1 million processor-hours.

Source: PhysOrg

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Over the weekend, Democratic senator Barack Obama made a public statement during his presidential campaign trail in Titusville, Florida. Whilst responding to a question about oceanic research, Obama elaborated on his plans for the future of NASA. Previously, there have been hints that a possible Obama Presidency would see a reduction in space funding in favour of a boost in education spending. However, Saturday's statement was followed by some detailed text on Obama's campaign blog outlining his priorities for the US dominance in space, the possibility of extending the Shuttle's operations and speeding up development of the Constellation program…

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Read the rest of The Politics of Space: Obama Wants to Increase NASA Funding
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It's been a busy few days for the Phoenix Mars lander rumour-mill. On Friday, an article was published in Aviation Week reporting an undisclosed source from the NASA team analysing results from the Microscopy, Electrochemistry, and Conductivity Analyzer (MECA) had come forward saying Phoenix scientists were in communication with the White House. Apparently there had been new, "provocative" results to come from the MECA, possibly a bigger discovery than last Thursday's announcement about the scientific proof of water in the Martian regolith.

Naturally, the blogosphere went crazy in response to this news. Yesterday, the Phoenix team issued a press release focussing on conflicting results from the MECA and Thermal and Evolved-Gas Analyzer (TEGA) instruments.

A MECA sample was found to contain a toxic substance known as perchlorate, usually an oxidizing by-product from industrial processes here on Earth.

However, a recently analysed sample from the TEGA turned up no supporting evidence for perchlorate. The study is ongoing. Today, the Phoenix team organized a press conference to discuss a more positive view on the possible discovery of perchlorate, and fired back at recent allegations that science was being withheld from the public…

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Read the rest of Perchlorate on Mars Could be Potential Energy Source for Life; Phoenix Team Fires Back at Allegations


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AND FROM spacweather.com

Earth is entering a broad stream of debris from Comet Swift-Tuttle, the source of the annual Perseid meteor shower. Although the shower does not peak until Tuesday, August 12th, don't be surprised to see a number of "early Perseids" making their appearance in the nights ahead: full story.

Have you seen the Lunar X? Once a month when the sun rises over Crater Werner in the Moon's southern hemisphere, sunlight floods the region's high terrain and makes a luminous criss-cross shape. Dana Thompson of Hebron, Ohio, sends this photo of an X he witnessed in Jan. 2007:

see link>www.spaceweather.com