A bird with a T. rex head may help reveal how dinosaurs became birds

A 120-million-year-old fossil bird found in China could offer some new clues about how landbound dinosaurs evolved into today’s flying birds. The dove-sized Cratonavis zhui sported a dinosaur-like head atop a body similar to those of today’s birds, researchers report in the January Nature Ecology & Evolution. The flattened specimen came from the Jiufotang Formation, […]

50 years ago, physicists found the speed of light

A group at the National Bureau of Standards at B­oulder, Colo., now reports an extremely accurate [speed of light] measurement using the wavelength and frequency of a helium-neon laser.… The result gives the speed of light as 299,792.4562 kilometers per second. UpdateThat 1972 experiment measured the two-way speed of light, or the average speed of […]

Climate change may be shrinking tropical birds

In a remote corner of Brazil’s Amazon rainforest, researchers have spent decades catching and measuring birds in a large swath of forest unmarred by roads or deforestation. An exemplar of the Amazon’s dazzling diversity, the experimental plot was to act as a baseline that would reveal how habitat fragmentation, from logging or roads, can hollow […]

Satellite swarms may outshine the night sky’s natural constellations

Fleets of private satellites orbiting Earth will be visible to the naked eye in the next few years, sometimes all night long. Companies like SpaceX and Amazon have launched hundreds of satellites into low orbits since 2019, with plans to launch thousands more in the works — a trend that’s alarming astronomers. The goal of […]