A very rare treat is about to grace Earth's night skies.

Potentially habitable exoplanets are so incredibly common that astronomers have started to consider more unusual situations ...

To understand what happened to Pluto, we must actually go back to the late 1700's, when a number of astronomers thought that there was something odd to the spacing of the planets orbiting the Sun.

To retain vast oceans similar to Earth, the planet would have to be about 10 AU away, or roughly the distance of Saturn from the sun. The second ... Generation Planets Orbiting White Dwarfs ...

TNOs are small bodies, or 'planetesimals,' orbiting the sun beyond Pluto. They never accreted into planets, and serve as pristine time capsules, preserving crucial evidence of the molecular ...

Read more: Full Moons Explained, From Blue Moons to Supermoons to Lunar Phases You won't have to wait long for all six planets to be in the sky. They'll be there as soon as the sun sets.

Asteroids are rocky objects left over from the early days of our solar system, orbiting the Sun much like planets. While most ...

Pluto, the most remote planet in our solar system, might be little more than a giant comet. Pluto resembles the icy, comet-like objects orbiting the Sun outside of Neptune's orbit, rather than ...