For the first time in decades, a new tiny moon has been found in orbit around the gas giant Neptune, according to a study published Wednesday in the journal Nature. Hippocamp, now known as Neptune’s ...

Astronomers have discovered a bizarre object in the outer solar system, 2020 VN40, that dances to Neptune’s gravitational beat in a never-before-seen rhythm. It’s the first of its kind, orbiting the ...

There may be a warp in the Kuiper Belt, possibly caused by “Planet Y” — a Mercury-to-Earth-sized world that orbits the sun way beyond the orbit of Neptune. Is there a mysterious “Planet Y” orbiting ...