Heavens

The new observations reveal that Messier 87's halo of stars has been cut short, with a diameter of about a million light-years, significantly smaller than expected, despite being about three times the extent of the halo surrounding our Milky Way [1]. Beyond this zone only few intergalactic stars are seen.

"This is an unexpected result," says co-author Ortwin Gerhard. "Numerical models predict that the halo around Messier 87 should be several times larger than our observations have revealed. Clearly, something must have cut the halo off early on."

STANFORD, Calif. — Human immune cells communicate constantly with one another as they coordinate to fight off infection and other threats. Now researchers at Stanford University's School of Medicine have shown that muffling a key voice in this conversational patter is an early step in the progression of human cancers. Silencing an inter-cell signaling mechanism called the interferon pathway may be one way newly developing cancers gain the upper hand. It may also explain the immune dysfunctions seen in many cancer patients and why cancer immunotherapies are often ineffective.

The study of ancient lake sediment from high altitude lakes in the Andes has revealed for the first time that mercury pollution occurred long before the start of the Industrial Revolution.

University of Alberta Earth and Atmospheric Sciences PhD student Colin Cooke's results from two seasons of field work in Peru have now provided the first unambiguous records of pre-industrial mercury pollution from anywhere in the world and will be published in the May 18th Early Edition of the Proceedings of the National Academy of Sciences (PNAS).

BERKELEY, CA — Members of the international Nearby Supernova Factory (SNfactory), a collaboration among the U.S. Department of Energy's Lawrence Berkeley National Laboratory, a consortium of French laboratories, and Yale University, have found a new technique that establishes the intrinsic brightness of Type Ia supernovae more accurately than ever before. These exploding stars are the best standard candles for measuring cosmic distances, the tools that made the discovery of dark energy possible.

Asian Americans who have adopted more aspects of Western culture may be more likely to engage in behaviors that increase sun exposure, thereby endangering their skin health, according to a report in the May issue of Archives of Dermatology, one of the JAMA/Archives journals.

STANFORD, Calif. - HIV-positive patients who don't seek medical attention until they have a serious AIDS-related condition can reduce their risk of death or other complications by half if they get antiretroviral treatment early on, according to a new multicenter trial led by researchers at the Stanford University School of Medicine.

The study results could lead to widespread changes in treatment for HIV patients, particularly those diagnosed at an advanced stage, experts say.

A phase III study has shown that adding an antibody-based therapy that harnesses the body's immune system resulted in a 20 percent increase in the number of children living disease-free for at least two years with neuroblastoma. Neuroblastoma, a hard-to-treat cancer arising from nervous system cells, is responsible for 15 percent of cancer-related deaths in children.

The two ends of a ruptured Achilles tendon are often stitched together before the leg is put in plaster, in order to reduce the risk of the tendon rupturing again. However, Katarina Nilsson Helander, MD, PhD at the Sahlgrenska Academy, University of Gothenburg, Sweden, now suggests that surgery may be unnecessary. Patients who do not undergo surgery have just as good a chance of recovery.

Alien creatures are the least of NASA's worries when it comes to moon travel. There are several potential threats to future missions - with space radiation at the top of the list. Now, a group of students at North Carolina State University has developed a "blanket" of sorts that covers lunar outposts - the astronauts' living quarters - to provide astronauts protection against radiation while also generating and storing power.

Imagine a time when the entire universe froze. According to a new model for dark energy, that is essentially what happened about 11.5 billion years ago, when the universe was a quarter of the size it is today.

The model, published online May 6 in the journal Physical Review D, was developed by Research Associate Sourish Dutta and Professor of Physics Robert Scherrer at Vanderbilt University, working with Professor of Physics Stephen Hsu and graduate student David Reeb at the University of Oregon.

Thanks to the ability of astronomers to detect the presence of extrasolar planets orbiting distant stars, scientists today are able to examine hundreds of solar systems. Now researchers at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. have created an "astro-comb" to help astronomers detect lighter planets, more like Earth, around distant stars.

When handling an emergency, firefighters are exposed to a number of risks: noxious fumes, blocked escape paths, potential building collapse. The safety of emergency crews and the efficient locating of persons buried under the rubble are key issues, and not only in the event of a major catastrophe, such as the collapse of the Cologne Historic Archives on March 3, 2009. Emergency managers have to know exactly where their teams are, and if they might be exposed to poisonous gases. Modern localization systems provide excellent service in this situation.

BLOOMINGTON, Ind. -- Research by a theoretical physicist at Indiana University shows that the crusts of neutron stars are 10 billion times stronger than steel or any other of the earth's strongest metal alloys.

Charles Horowitz, a professor in the IU College of Arts and Sciences' Department of Physics, came to the conclusion after large-scale molecular dynamics computer simulations were conducted at Indiana University and Los Alamos National Laboratory in New Mexico. The research will appear Friday (May 8) in Physical Review Letters.

Since its launch last June, NASA's Fermi Gamma-ray Space Telescope has discovered a new class of pulsars, probed gamma-ray bursts and watched flaring jets in galaxies billions of light-years away. Today at the American Physical Society meeting in Denver, Colo., Fermi scientists revealed new details about high-energy particles implicated in a nearby cosmic mystery.