Geoff Brumfiel

North Korea's bombastic propaganda and unpredictable leadership have made it a topic of frequent parody. But experts say it's time to take the nation's nuclear capabilities more seriously.

Five years after meltdowns at the Fukushima Dai-ichi nuclear power plant in Japan, progress has been made, but there's still plenty to do.

On Wednesday in South Korea, a Google AI program will take on a top-level player in the ancient game of Go. Here's what you need to know.

NASA astronaut Scott Kelly and Russian cosmonaut Mikhail Kornienko spent most of a year on the International Space Station. Their landing brings an epic mission to an end.

During his 340 days aboard the International Space Station, the astronaut documented his time there with hundreds of photos. Kelly says the perspective makes him feel like an environmentalist.

"I have taken a lot of pictures because I've been up here for a long time," NASA astronaut Scott Kelly said during a recent press conference from the International Space Station. "I've definitely taken some good ones and some memorable ones."

When he returns to Earth on Tuesday evening, ...

A new study suggests that sea levels are rising at an unprecedented rate and that the problem will continue well into this century.

"Sea level rise in the 20th century was truly extraordinary by historical standards," says Bob Kopp, an associate professor of Earth and planetary sciences at Rutgers ...

A decade after phasing out celestial navigation from its academy courses, the U.S. Navy has restarted that formal training. The shift comes at a time of growing anxiety over possible threats to GPS.

On Thursday, researchers announced the discovery of gravitational waves --wrinkles in the very fabric of space-time.

But behind the headlines and news conferences were decades of hard work, hundreds of scientists and more than a billion dollars in taxpayer funds.

"It's profoundly satisfying that it came out the way ...

Scientists have seen gravitational ripples from two black holes colliding. The discovery is the culmination of decades of work. Albert Einstein first predicted such ripples should exist a century ago.

A U.S.-led team says it has seen waves in space-time from two black holes merging together. It is the first time humanity has directly detected such waves.

Researchers may have detected gravitational ripples from the collision of two black holes, according to rumors circulating in emails and on blogs.

The Laser Interferometer Gravitational-Wave Observatory (LIGO) is planning a major announcement for Thursday morning. For now, scientists directly involved in the project are staying quiet ...

A computer has bested humanity at one of the most complex strategy games ever devised.

Researchers at Google have developed a program that can excel at the game of "go," which originated in China and is considered a tougher problem for a machine than other strategy games such as ...

In a NASA facility just outside Washington, D.C., workers are building the James Webb Space Telescope, an $8 billion successor to the Hubble. It'll be the largest ever, and it's set to launch in 2018.

Scientists analyzed the tummy of a 5,300-year-old ice mummy and found bacteria that many modern humans still carry.

North Korea says it detonated a powerful hydrogen bomb on Wednesday. But the White House says it doesn't believe the claim.

SpaceX, the commercial aerospace company, pulled off a major feat Monday night. After pushing satellites towards orbit, the rocket's booster separated, and safely landed back on earth.

A new report from the International Atomic Energy Agency details the covert program, which ran until 2003. But experts say the findings are unlikely to derail Iran's nuclear deal with world powers.

Commercial space startup Blue Origin announced Tuesday the successful launch and landing of one of its rockets. NPR explores what the success means for space travel.

A random search has turned up a dwarf planet orbiting roughly 10 billion miles away. The far-off world is tiny, and probably very, very cold.