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Scientists are trying to figure out how green-blooded lizards might benefit from the unusual pigment. The answer could provide new insights into human illnesses like jaundice and malaria.

In 2015, to great fanfare, NASA announced a planet discovery considered a milestone in the hunt for another Earth. But now some researchers say it's not clear that this planet actually exists.

The European Space Agency has released a chart of the exact positions of many stars in the Milky Way and neighboring galaxies. But the map only shows a small fraction of what's out there.

NASA is launching a mission to find Earth-sized planets beyond our solar system that scientists can study for signs of life. Scientists already know of over 3,000 planets around distant stars.

The supermassive black hole lurking at the center of our galaxy appears to have a lot of company, according to a new study that suggests the monster is surrounded by about 10,000 other black holes.

In 1996, Congress limited the Centers for Disease Control and Prevention's ability to study gun control. That will change with the new budget, but gun violence researchers aren't impressed.

Some say the new appropriations bill contains language that will free up the Centers for Disease Control and Prevention to do more gun violence research, but others are more skeptical that anything will change.

Most of the Chinese space lab, the size of a city bus, will burn up in the atmosphere, but some debris may survive re-entry.

E.coli bacteria, each cell trapped in a tiny tube, are giving researchers the chance to study the pace and effects of single genetic mutations. Most mutations, the scientists find, aren't harmful.

A new study suggests that the early universe got an unexpectedly cold start, and that dark matter may be to blame.

A story from the journal Science suggests that the only "wild" horses in existence aren't actually wild at all but rather are the feral descendants of an early domestication.

Private company SpaceX on Tuesday is set to launch the world's most powerful rocket — the Falcon Heavy. This is a test launch that will carry a cherry red Tesla roadster into orbit around Mars.

The company is getting ready for the first flight of its massive Falcon Heavy. It will be the most powerful rocket in use — if it doesn't blow up.

Given a choice, bonobos tend to prefer people who act like jerks and dominate. That's very different than humans, who even as infants consistently prefer people who are cooperative and not mean.

A giant whale eye spent decades on a strange journey before it finally arrived at an animal eyeball lab and gave the folks there the "best Christmas ever."

After an unusual three-year moratorium, the federal government says it will once again allow research on deadly viruses that could spark pandemics. The work has sparked concerns about bioterrorism.

After being caught in a net, narwhals appear to get confused about what to do. Researchers say the whales' befuddlement could provide clues about how they will adapt to a changing Arctic.

Senators are about to get their chance to grill the nominee for head of the National Oceanic and Atmospheric Administration. Critics say he has a conflict of interest.

Billions of these birds once flew over North America, but the last known passenger pigeon died in 1914. To try to figure out what happened, scientists analyzed DNA from the toes of birds in museums.

Researchers used equipment that detects muons. Measuring the density of the tiny particles yielded an image of what's behind the pyramid walls with no damage to the ancient structure.