Earth’s dry regions have more trees than once thought — a hopeful note in the fight against climate change. An analysis of high-resolution satellite imagery reveals that drylands globally have 40 to 47 percent more tree cover (an extra 467 million hectares) than reported in earlier estimates. An international team of researchers used Google Earth […]

John Archibald Wheeler was fond of clever phrases. He made the term “black hole” famous in the 1960s. He also coined the now-familiar “wormhole” and “quantum foam.” While further pondering the mystery of quantum physics at the University of Texas at Austin during the 1980s, Wheeler repeatedly uttered his favorite interrogative slogan: “How come the […]

The Juno spacecraft’s first closeup views of Jupiter’s Great Red Spot are here. The spacecraft flew just 9,000 kilometers above the famous storm on July 10. Scientists had expected the images to take until at least the night of July 13 to download because the spacecraft’s antenna was pointed away from Earth. But the first […]

Ravens have passed what may be their toughest tests yet of powers that, at least on a good day, let people and other apes plan ahead. Lab-dwelling common ravens (Corvus corax) in Sweden at least matched the performance of nonhuman apes and young children in peculiar tests of advanced planning ability. The birds faced such […]

Walls can’t talk, but scientists can now read stories written in their subatomic particles. And that could make it harder to store radioactive material in secret. Nuclear radiation rearranges the electrons in insulators such as brick, glass and porcelain. So comparing the positions of electrons in atoms at different spots on walls, windows and floors […]

Rowa Mohammed Assayaghi teaches people how to wash their hands. In Yemen, that’s life-saving work. The Middle Eastern country is facing the world’s largest cholera outbreak, with nearly 409,000 suspected cases and 1,885 deaths from late April to late July, the World Health Organization reports. That tally is higher than 2015’s worldwide reported cholera deaths. […]

The star of any solar eclipse is, of course, the sun. And total eclipses give the sun’s wispy, tenuous atmosphere the spotlight. This region, called the corona, is normally too dim to observe directly. But with the moon blocking the sun’s bright disk, the corona comes into view. And the view is dazzling. The corona’s […]

Take a bow, Cassini. It’s been a marathon performance: 20 years in space, more than 200 orbits around Saturn, and hundreds of thousands of images of the giant planet, its splashy rings and its many moons. On September 15, the veteran spacecraft will use its last burst of fuel to plunge into the sixth planet […]

Islamic militants and their fiercest opponents fight and die for intensely spiritual reasons, a new report finds. Islamic State (also known as ISIS) soldiers and Kurds who have fiercely battled them sacrifice themselves for sacred, nonnegotiable values, says a team led by anthropologist Scott Atran of the University of Michigan in Ann Arbor. These soldiers’ […]