In an undated rendering from NASA, a concept image of a lunar surface nuclear reactor. Sean Duffy, the acting administrator of NASA, has...

In an undated image provided by Tobias Wilhelm/State Museum of Natural History Stuttgart, an artist’s reconstruction of Mirasaura, which...

A frame from a video provided by Nadine Holmes shows an ocelot and an opossum together in the Amazon. Scientists are trying to understand...

John Christy, an atmospheric scientist who doubts that human activity has caused global warming, in 2014. The Energy Department has hired...

In an undated image provided by David Rankin/Saguaro Observatory, A11pl3Z captured by David Rankin, an engineer at the Catalina Sky...

To Dave Ebert, a shark scientist at San Jose State University, the movie brought sharks out of the shadows, where they had been...

The installation of the stegosaurus fossil nicknamed Apex, known for the plates that line its back, at the American Museum of Natural...

In an undated image provided by Tom Björklund, an artist’s interpretation of the LRJ people, who lived across northern Europe about...

In an undated image provided by Eric Carlson/Desert Archaeology, Inc.; Ben Potter/University of Alaska Fairbanks and Jim...

By Jim Robbins Hummingbirds zooming around the garden from flower to flower and sipping nectar probably don’t appear at first glance to...