Astronomers are closing in on one of the most tantalizing possibilities in planetary science, evidence that a previously ...

3I/ATLAS has now made its closest approach to the sun and Earth and is now heading back out toward the outer solar system. On ...

For the first time since Pluto was demoted, the idea of a true ninth planet is edging from speculation toward something ...

The upcoming year will offer a blood-red moon, spectacular meteor showers and the first glimpse of the sun’s corona since ...

The newly identified cluster of Kuiper Belt objects lies about 4 billion miles from the Sun, offering fresh clues about how ...

Mercury has long baffled astronomers because it defies much of what we know about planet formation. A new space mission ...

A new study has proposed the existence of Planet Y, an alternative Planet Nine candidate that is smaller and closer to Earth than the hypothetical Planet X, which astronomers have been hunting for ...

CAPE CANAVERAL, Fla. (AP) — Astronomers have discovered the earliest seeds of rocky planets forming in the gas around a baby sun-like star, providing a precious peek into the dawn of our own solar ...

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 ...

Could the icy moons of our solar system hold life beyond our planet? Keith Cooper looks at how planetary scientists plan to ...

For More Webcasts: http://www.nasm.si.edu/webcasts/archive.cfm?siref=YouTube&video=PlutoErisDwarfPlanets Pluto, Eris, and the Dwarf Planets of the Outer Solar System ...