Science

Angela Stimpson donated a kidney to a complete stranger. Why did she do it? Researchers found that the brains of Stimpson and other altruists are sensitive to fear and distress in a stranger's face.

The People's Climate March was timed to draw the notice of world leaders gathering for this week's U.N. Climate Summit in New York.

NASA's MAVEN spacecraft on Sunday night fired its six main rocket engines for 33 minutes. That slowed the probe down enough so it could be captured by the Red Planet's gravity.

Is Democracy a key to better levels of health in a country? That's long been the belief, but we hear about some research that shows that isn't always the case.

Scientists hope NASA's MAVEN probe, which went into orbit Sunday night, will provide insight into why the Martian climate changed drastically billions of years ago.

Hundreds of thousands are expected at a march in New York City ahead of the United Nations climate summit. Organizers want to send a message to world leaders that it's time to take concrete action.

Earlier this week, NASA awarded two contracts for new spaceships to commercial companies. Here's how they compare.