Astronomers have identified a quartet of small rocky planets orbiting Barnard's star - one of our closest stellar neighbors - ...

(Correction: An earlier version of this story misstated how far Pluto is from the sun. The correct number is 3.7 billion miles.) What was discovered in Flagstaff, Arizona, and killed off in Prague?

A spacecraft operated by the European Space Agency and the Japan Aerospace Exploration Agency has made its final flyby of Mercury, as scientists now work to guide BepiColombo into the planet’s ...

Caltech researchers have mathematical evidence suggesting a Neptune-sized Planet X may exist deep in the solar system in an orbit far beyond Pluto. Planet X could have a mass about 10 times that of ...

Located in Nagaizumi, Japan, this tiny park is the size of four pieces of paper—and it just set a Guinness World Record as the smallest in the world.

From brutal depletion to a promising rebound, the North Pole’s ozone recovery brings hope to a planet yearning for a comeback story. The notorious Polar Vortex concentrates chemicals that eat ...