Heavens

Spiral galaxies are some of the most beautiful and photogenic residents of the universe. Our own Milky Way is a spiral. Our solar system and Earth reside somewhere near one of its filamentous arms. And nearly 70 percent of the galaxies closest to the Milky Way are spirals.

But despite their common shape, how galaxies like ours get and maintain their characteristic arms has proved to be an enduring puzzle in astrophysics. How do the arms of spiral galaxies arise? Do they change or come and go over time?

A team of astronomers led by the International Centre for Radio Astronomy Research (ICRAR) have succeeded in observing the death throws of a giant star in unprecedented detail.

ANN ARBOR, Mich. — Do cash rewards for healthier habits work? Maybe, says a new study, if you add on one more condition – peer pressure.

A growing number of companies are offering employees an opportunity to boost earning power at work via cash incentives to stay healthy. Under the Affordable Care Act, employers will soon be able to offer even larger financial incentives to prod healthy lifestyle behaviors among their workforce, such as quitting smoking and losing weight.

Anyone who has spent more than a few minutes watching some of the more partisan "news" networks lurking in the bowels of cable television is aware that America has grown more polarized in recent years. What's not so certain is why. In a paper published online March 27 in the Proceedings of the National Academy of Sciences (PNAS), a team of researchers at Stanford has devised a mathematical model that helps demonstrate what's behind the growing rift.

Hint: It's you, not them.

The Jan. 30 UVOT observations reveal that ISON was shedding about 112,000 pounds (51,000 kg) of dust, or about two-thirds the mass of an unfueled space shuttle, every minute. By contrast, the comet was producing only about 130 pounds (60 kg) of water every minute, or about four times the amount flowing out of a residential sprinkler system.

Human cells have an intrinsic capacity to destroy HIV. However, the virus has evolved to contain a gene that blocks this ability. When this gene is removed from the virus, the innate human immune system destroys HIV by mutating it to the point where it can no longer survive.

Messier 77 is a galaxy in the constellation of Cetus, some 45 million light-years away from us. Also known as NGC 1068, it is one of the most famous and well-studied galaxies. It is a real star among galaxies, with more papers written about it than many other galaxies put together!

Managing bacteria and other microorganisms in the body, rather than just fighting them, may be lead to better health and a stronger immune system, according to a Penn State biologist.

Researchers have historically focused on microbes in the body as primarily pathogens that must be fought, said Eric Harvill, professor of microbiology and infectious disease. However, he said that recent evidence of the complex interaction of the body with microbes suggests a new interpretation of the relationship.

Prebiotic supplements in infant formula may help to prevent eczema, according to a systematic review published in The Cochrane Library. However, the review highlights a lack of high quality evidence for the effects of prebiotics in preventing allergies.

An international team of astronomers, including researchers from the Max Planck Institute for Radio Astronomy and from the University of Cologne, successfully identified two titanium oxides in the extended atmosphere around a giant star. The object VY Canis Major is one of the largest stars in the known universe and close to the end of its life. The detection was made using telescope arrays in the USA and in France.

Homes and buildings chilled without air conditioners. Car interiors that don't heat up in the summer sun. Tapping the frigid expanses of outer space to cool the planet. Science fiction, you say? Well, maybe not any more.

Now, a group of researchers led by two astronomers at the University of Toronto suggests that baby stars may grow to great mass if they happen to be born within a corral of older stars –with these surrounding stars favorably arranged to confine and thus feed gas to the younger ones in their midst. The astronomers have seen hints of this collective feeding, or technically "convergent constructive feedback," in a giant cloud of gas and dust called Westerhout 3 (W3), located 6,500 light years from us. Their results are published in April in The Astrophysical Journal.

Research from the University of Cincinnati just published in the March issue of the Journal of Environmental Assessment Policy and Management measures the impact of brownfields on nearby residential property values in the City of Cincinnati. (Brownfields are abandoned business or industrial sites with either potential or proven on-site pollutants.)

The Universe is an old neighbourhood -- roughly 13.8 billion years old. Our galaxy, the Milky Way, is also ancient -- some of its stars are more than 13 billion years old (eso0425). Nevertheless, there is still a lot of action: new objects form and others are destroyed. In this image, you can see some of the newcomers, the young stars forming the cluster NGC 2547.

When the Mars Atmosphere and Volatile Evolution (MAVEN) mission begins its journey to the Red Planet in 2013, it will carry a sensitive magnetic-field instrument built and tested by a team at NASA's Goddard Space Flight Center in Greenbelt, Md.

Scheduled for launch in late 2013, MAVEN will be the first mission devoted to understanding the Martian upper atmosphere.

The goal of MAVEN is to determine the history of the loss of atmospheric gases to space through time, providing answers about Mars' climate evolution.