The long, shallow grooves lining the surface of Phobos are likely early signs of the structural failure that will ultimately destroy this moon of Mars.

Orbiting a mere 3,700 miles (6,000 kilometers) above the surface of Mars, Phobos is closer to its planet than any other moon in the solar system. Mars' gravity is drawing in Phobos, the larger of its two moons, by about 6.6 feet (2 meters) every hundred years. Scientists expect the moon to be pulled apart in 30 to 50 million years.

"We think that Phobos has already started to fail, and the first sign of this failure is the production of these grooves," said Terry Hurford of NASA's Goddard Space Flight Center in Greenbelt, Maryland.

A team of physicists led by Stephen Jardin of the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) has discovered a mechanism that prevents the electrical current flowing through fusion plasma from repeatedly peaking and crashing. This behavior is known as a "sawtooth cycle" and can cause instabilities within the plasma's core. The results have been accepted for publication in Physical Review Letters. The research was supported by the DOE Office of Science (Office of Fusion Energy Sciences).

Childhood cancer survivors are at heightened risk of a wide range of autoimmune diseases, reveals research published online in the Annals of the Rheumatic Diseases.

Diabetes and Addison's disease--a condition in which the adrenal gland doesn't work properly--make up almost half of the excess cases, the findings show.

Over the past 40 years, the number of childhood cancer survivors has risen sharply, resulting in a five year survival rate of 80% among children who succumb to the disease.

But mounting evidence suggests that these survivors are at heightened risk of various health problems as adults, which increase in number and severity as they get older.

In 2006, a tiny percentage of astronomers took it upon themselves to change the definition of "planet" and so Pluto was out. Chaos ruled, the 237 astronomers who made the ruling dug in their heels, and for the most part they were ignored.

After all, there are now nearly 5,000 planetary bodies orbiting stars other than ours. But astronomers don't know what exactly we should call them. Today at an American Astronomical Society meeting, UCLA professor Jean-Luc Margot described a simple test that can be used to clearly separate planets from other bodies like dwarf planets and minor planets and replace the  "definitional limbo" those bodies are in. 

A new cholesterol-lowering vaccine leads to reductions in 'bad' LDL cholesterol in mice and macaques, according to research published in Vaccine. The authors of the study say the vaccine has the potential to be a more powerful treatment than statins alone.

The body produces cholesterol to make vitamin D, some hormones and some of the molecules that help us digest food. Cholesterol is also found in foods. LDL cholesterol is a fat-like substance that circulates in the blood; if there is too much cholesterol, the arteries can become blocked, leading to heart disease and stroke.

Though 97 percent of climate experts believe in climate change, the public remains less convinced, including teens, who are most likely to believe what they are told and so are heavily marketed toward. Only 46 percent of teens think climate change is anything but a natural fluctuation while 57 percent aren't concerned about it.

Humanities scholar Diego Román of Southern Methodist University thinks more control over textbook content used by teachers is the answer. A new study measured how four sixth-grade science textbooks adopted for use in California frame the subject of global warming. Sixth grade is the first time California state standards indicate students will encounter climate change in their formal science curriculum.

An international research team has a hypothesis regarding the mystery of why the Mediterranean Sea dried up around 5.6 million years ago. The event, known as the Messinian Salinity Crisis (MSC), saw the Mediterranean become a 1.5 kilometer deep basin for around 270,000 years, and left a kilometers-deep layer of salt due to seawater evaporation.

The cause of the MSC has been the subject of speculation and debate, but now an international team of researchers

Researchers have identified factors that spark the formation of pluripotent cells. Their findings, published in Developmental Cell, shed light on human embryonic development and help research into cell reprogramming and assisted conception.

Genetic sequencing of a single tumor reveals far greater genetic diversity among cancer cells than anticipated. Researchers from the University of Chicago and the Beijing Institute of Genomics estimate that the tumor, about 3.5 centimeters in diameter, contained more than 100 million distinct mutations within the coding regions of its genes--thousands of times more than expected.