Astronomers have discovered a giant Saturn-sized planet orbiting TOI-6894, the smallest star ever known to host such a world. The finding overturns long-held theories suggesting that tiny, low-mass ...

Astronomers have identified a strikingly large gas giant orbiting a remarkably small red dwarf star — a finding that challenges long-standing assumptions about how planetary systems form. The ...

NASA bragged Tuesday that its Kepler Space Telescope had discovered the two smallest planets ever found orbiting a distant star, but a UA astronomer and colleagues may have discovered even smaller ...

Mercury is the smallest planet in our solar system. Explore its size, extreme temperatures, core structure, and comparison with Pluto.