Dwarf planet 2023 KQ14, Ammonite, has a stable orbit that challenges the hypothesis of the mysterious Planet Nine.

There could be a ninth planet in our Solar System after all - and no, it's not Pluto. Instead, it's the theoretical Planet X, also called Planet Nine, a wide-orbit planet that would circle the Sun ...

A new "Tatooine-like" planet outside the solar system may orbit two failed stars, scientists reported Wednesday.Related video above: The dark energy pushing our universe apart may not be what it seems ...