Trans-Neptunian objects (TNOs) are icy bodies that vary widely in size, from large dwarf planets like Pluto and Eris—each ...

A new study examines how much material from the closest star system to Earth will end up in orbit around the Sun, and how ...

Mars, Venus, Jupiter and Saturn should be visible to the naked eye, but with a telescope you can spot Neptune and Uranus.

For decades, we believed there were nine planets in our solar system—until Pluto was reclassified in 2006. But what if ...