The Death Star of the movie Star Wars may be fictional, but planetary destruction is real. Astronomers announced today that they have spotted a large, rocky object disintegrating in its death spiral around a distant white dwarf star. The discovery also confirms a long-standing theory behind the source of white dwarf "pollution" by metals.

"This is something no human has seen before," says lead author Andrew Vanderburg of the Harvard-Smithsonian Center for Astrophysics (CfA). "We're watching a solar system get destroyed."

When a star comes too close to a black hole, the intense gravity of the black hole results in tidal forces that can rip the star apart. In these events, called tidal disruptions, some of the stellar debris is flung outward at high speeds, while the rest falls toward the black hole. This causes a distinct X-ray flare that can last for years.

A team of astronomers has observed a tidal disruption event in a galaxy that lies about 290 million light years from Earth, the closest tidal disruption discovered in about a decade.

In 1939, a Russian engineer proposed a "flying submarine" -- a vehicle that can seamlessly transition from air to water and back again. While it may sound like something out of a James Bond film, engineers have been trying to design functional aerial-aquatic vehicles for decades with little success. Now, engineers may be one step closer to the elusive flying submarine.

The biggest challenge is conflicting design requirements: aerial vehicles require large airfoils like wings or sails to generate lift while underwater vehicles need to minimize surface area to reduce drag.

Vaccines help prevent disease by inducing immunological memory, the ability of immune cells to remember and respond more quickly when re-exposed to the same pathogen. While certain phases of the pathway are well understood, little is known about the role of helper T cells, a "master orchestrator" of the immune response that send signals to activate the immune system.

A study has identified molecular mechanisms that control an immune cell's ability to remember. They found that in helper T (CD4+) cells, the proteins Oct1 and OCA-B work together to put immune response genes on standby so that they are easily activated when the body is re-exposed to a pathogen.

Women with particularly aggressive forms of breast cancer could be identified by a test that predicts whether the disease is likely to spread to the brain.

An analysis of almost 4,000 patients with breast cancer found that testing for high activity in a particular gene called alpha beta (αB)-crystallin could pick out women who were at greater risk of developing secondary brain tumors compared to women who tested negative.

A team including scientists at The Institute of Cancer Research, London, found that women whose breast cancer had begun to spread and who tested positive in the αB-crystallin test were three times more likely to have disease that spread to the brain than those who tested negative.

Chemical signaling among social insects, such as bees, ants and wasps, is more complex than previously thought, according to researchers whose results refute the idea that a single group of chemicals controls reproduction across numerous species.

Processing fabric for the latest fashions and other textile-based products today requires thousands of chemicals, some of which are toxic and cause 20 percent of the world's water pollution. To reduce its environmental footprint, the textile industry is making changes, designing safer chemicals and turning to nature to find replacements to potentially harmful compounds, according to an article in Chemical&Engineering News.

Girls from families with a history of breast cancer, or genetic mutations that increase the risk of a breast cancer diagnosis, seem to adjust just as well as other girls when it comes to general anxiety, depression and overall psychosocial adjustment, according to new research from the Perelman School of Medicine at the University of Pennsylvania and the Children's Hospital of Philadelphia. However, the study also found that girls from at-risk families tend to worry more about breast cancer, particularly when their mothers have the same worries. 

Botulinum toxin, commonly known as Botox, is produced by Clostridium botulinum bacteria and was once known for disease but is now known for making Hollywood actresses look plastic. However, it may also prevent irregular heart rhythms when injected into fat surrounding the heart after bypass surgery, according to research in Circulation: Arrhythmia and Electrophysiology.

When a small amount of Botox is injected into a muscle, it blocks nerve signals that tell muscles to contract. Atrial fibrillation (also called AFib or AF) is a quivering or irregular heartbeat (arrhythmia) that can lead to blood clots, stroke, heart failure and other heart-related complications.

Scientists have identified a new way to stop the growth of lung cancer cells, by blocking their ability to use alternative sources of nutrition. The discovery was made possible by identifying the metabolic programs used by cancer cells to fuel their growth. The findings point to possible new avenues for treating lung cancer, which is the second most common cancer and accounts for over one-quarter of all cancer-related deaths. The results of the study were published Oct. 15 in the journal Molecular Cell.