New research suggests that a binary pair of Kuiper Belt objects, known as the Altjira system, is actually made up of three ...

In January 2025, Venus, Mars, Jupiter, Saturn, Uranus and Neptune were all visible in the night sky. And in February, 2025, Mercury will join the fun, with all seven of our planetary neighbors visible ...

Astronomers have made an extraordinary discovery—for the first time, scientists have directly observed two alien planets ...

Pluto was discovered 95 years ago on Feb. 18, and even though it was demoted nearly two ... Planet X. Using a tool called a blink comparator, Tombaugh finally found the mysterious body in 1930.