His SpaceX rocket-launch company is considering an IPO that would value the business at about $1.5 trillion, according to ...

Astronomers have discovered icy rocks in the outer solar system that challenge the known laws of physics, suggesting the ...

LONDON — The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper's authors have ...

This artistic photo compilation compares the size of Planet Nine (right) to Earth (left). Dr. Konstantin Batygin, professor of Planetary Science at Caltech, made a joke that turned out to be true. In ...

On August 24, 2006, our solar system lost a planet. It wasn't by cataclysmic destruction, but rather by the vote of the International Astronomical Union, which declared that Pluto, considered the ...

Forbes contributors publish independent expert analyses and insights. An award-winning reporter writing about stargazing and the night sky. 2023 KQ14, nicknamed “Ammonite,” is a trans-Neptunian object ...

Think you can spot Pluto? On July 25, the famously elusive dwarf planet reaches opposition—its best and brightest moment of the year. That makes now the ideal time to try to catch a glimpse of it from ...

The trans-Neptunian object nicknamed Ammonite moves across the sky over several hours in May 2023. Its diameter is estimated to be between about 135 and 235 miles. NAOJ / ASIAA Astronomers have just ...