New images from NASA's Chandra X-ray Observatory and ESA's XMM-Newton, have helped astronomers detect a vast reservoir of intergalactic gas about 400 million light years from Earth. This discovery is the strongest evidence yet that the “missing matter” in the nearby Universe is located in an enormous web of hot, diffuse gas.

A Texas A&M University-led team of astronomers has uncovered what may be the earliest, most distant cluster of galaxies ever detected.

The group of roughly 60 galaxies, called CLG J02182-05102, is nearly 10 billion years old — born just 4 billion years after the Big Bang. However, it's not the size nor the age of the cluster that astronomers find amazing. Rather, it's the surprisingly modern appearance of CLG J02182-05102 that has them baffled — a huge, red collection of galaxies typical of only present-day galaxies.

"It's like we dug an archaeological site in Rome and found pieces of modern Rome amongst the ruins," explains Dr. Casey Papovich, an assistant professor in the Texas A&M Department of Physics and Astronomy.

Computer analysis of sentiments expressed in a billion "tweets" during 2008-2009 yielded measures of consumer confidence and presidential job approval similar to those of well-established public opinion polls, Carnegie Mellon University researchers say.

The findings suggest that analyzing the text found in streams of tweets could become a cheap, rapid means of gauging public opinion on at least some subjects. But tools for extracting public opinion from social media text are still crude and social media remain in their infancy, so the extent to which these methods could replace or supplement traditional polling is still unknown.

Working overtime may be bad for your heart, according to results from a long-running study following more than 10,000 government employees in London.

The research, published in the European Heart Journal, found that, compared with people who did not work overtime, people who worked three or more hours longer than a normal, seven-hour day had a 60% higher risk of heart-related problems such as death due to heart disease, non-fatal heart attacks and angina.

Researchers warn, however, that there study did not include any private sector employees and cannot be generalized as a result.

A 150 million year old Archaeopteryx fossil, long thought to contain nothing but fossilized bone and rock, has been hiding remnants of the animal's original chemistry, say researchers writing in PNAS. The find provides a chemical link between dinosaurs and modern birds, The authors say.

"Archaeopteryx is to paleontology what Tutankhamen is to archaeology. It's simply one of the icons of our field," said University of Manchester paleontologist Phil Manning. "You would think after 150 years of study, we'd know everything we need to know about this animal. But guess what—we were wrong."

For decades, the consensus among psychologists was that young children adopt an "anthropocentric" stance, favoring humans over non-human animals, when they begin reasoning about the biological world.

But a new study published in Cognitive Development reveals that this style of human-centered reasoning is not universal.

 The study included children growing up in an urban setting (Chicago) as well as children from rural Wisconsin, who have more extensive direct contact with the natural world. To examine the influence of culture, the rural community included European-American and Native American (Menominee) children.