New evidence shows that, far beyond Pluto, there may exist a hypothetical planet referred to as Planet X or Planet Nine.

New telescope images show interstellar comet 3I/ATLAS brightening and turning green after solar heating, raising questions ...

Interstellar comet 3I/ATLAS shows a growing green glow and new X-ray activity as scientists study changes in its chemistry during its rare passage through the Solar System ...

NASA’s Hubble Telescope photographed the comet on November 30. At that time, the comet was still very far — about 178 million ...

A NASA spacecraft is making a close approach to the sun, repeating its record-breaking distance of 3.8 million miles from the ...

Researchers at the University of Hawaiʻi Institute for Astronomy (IfA) are helping reshape how scientists study the sun. The ...

Interstellar comet 3I/ATLAS is making its closest approach to Earth, sparking a fierce debate. Harvard's Avi Loeb argues its ...

Learn what the first maps of the sun's atmospheric boundary reveal about solar wind and its escape into space.

If future missions confirm sustained heat flow at both poles, Enceladus would strengthen its position as one of the more accessible environments for detecting extraterrestrial life within the Solar ...

Astronomers have created the first continuous, two-dimensional maps of the outer edge of the Sun’s atmosphere, revealing a ...

Up to 150 Geminid meteors may brighten the night sky each hour as the shower hits its peak on Dec. 13-14, according to the ...