Astronomers discover Ammonite, a rare icy object beyond Pluto, challenging Planet Nine theory and offering clues to the solar system’s ancient origins.

The Dutch-led team used NASA's Webb Space Telescope and a telescope in Chile to observe a young star some 1,370 light-years away.

Astronomers have discovered the earliest seeds of rocky planets forming in the gas around a baby sun-like star, providing a ...

Astronomers discovered evidence for the earliest stages of planet formation forming around a baby sun-like star, providing a ...

"It is possible that a planet once existed in the solar system but was later ejected, causing the unusual orbits we see today." ...

In the remote outer reaches of planetary systems, far beyond the orbit of known planets, enormous and mysterious worlds silently loop around their stars. Some drift as far as 10,000 times the ...

This new dwarf planet may exist at the edge of the solar system, possibly disproving Planet Nine's existence. This is the story of that newly encountered planet.

Back to Article List Does our solar system have a new dwarf planet? The recently discovered object has a diameter about one-third that of Pluto.