Learn how a possible ninth planet, the theoretical Planet X, could have acquired its wide orbit in the outer Solar System — a process that’s also applicable for other planets. There could be a ninth ...

A tiny object far beyond Pluto, newly discovered by the Subaru Telescope, could reshape our understanding of the early Solar System. Named 2023 KQ14, this rare “sednoid” follows an unusual orbit that ...

Now that its reflective sail has deployed fully open in orbit, the Advanced Composite Solar Sail System can be seen in the night sky from many locations across the world! Can you spot the solar sail?

Astronomers have uncovered a massive new trans-Neptunian object, 2017 OF201, lurking at the edge of our solar system. With an orbit stretching 25,000 years and a size that may qualify it as a dwarf ...