Geoff Brumfiel

Donna Strickland seemed genuinely surprised to learn that she was only the third woman to ever win the Nobel Prize in physics.

"Is that all, really?" a flummoxed Strickland asked during a press conference announcing the prize. "I thought there might have been more."

It's a terrifying weapon: a nuclear-powered cruise missile that can fly anywhere on the planet, possibly spewing radioactivity as it goes. In March, Russian President Vladimir Putin announced that his nation had successfully tested just such a machine.

But new satellite imagery of a remote Russian test site suggests that the missile may not be working as well as claimed.

North Korea announced today that it will permanently close a major missile test site. Kim Jong Un, the North's leader, said the site would be dismantled in the presence of international inspectors.

A Swiss laboratory likely involved in analyzing samples from a March chemical attack in Salisbury, England, has reportedly been targeted by Russian agents.

Experts have been left scratching their heads over one of the most concrete concessions President Trump says he received from North Korean leader Kim Jong Un during Tuesday's summit in Singapore.

At a press conference after their meeting, Trump said Kim had agreed to destroy "a major missile engine testing site."

Updated: 10:45 a.m. ET

North Korea closed its nuclear test site in spectacular fashion Thursday, blasting the site in what one observer described as a "huge explosion."

NASA and the U.S. Department of Energy say they have successfully tested a new type of nuclear reactor that could one day provide juice to colonies on other worlds. The reactor can power several homes and appears able to operate in harsh environments.

Former weapons inspectors say an apparent trove of information on Iran's nuclear weapons program will increase pressure for more intrusive inspections of its atomic sites.

On Monday, the Israeli government disclosed it had obtained thousands of pages of documents and nearly 200 CDs' worth of data on Iran's nuclear program.

As chemical weapons inspectors wait to investigate an alleged strike near the Syrian capital of Damascus, former inspectors say the challenges the current team faces are daunting.

The inspectors arrived in Syria on April 14, on a mission to investigate a suspected chemical attack in the Damascus suburb of Douma seven days earlier. Unconfirmed reports from the scene suggest that dozens may have died.