The number of planets that orbit the sun depends on what you mean by “planet,” and that’s not so easy to define ...

Does our Solar System have 9 planets or only 8? Astronomers have gone back and forth on that a lot, with Pluto now being classified as a dwarf planet. However, out beyond Neptune there could be ...

Filmmaker Adam Nemoy helps celebrate the 90th anniversary of Pluto's discovery this month at the 6th annual 'I Heart Pluto' ...

Scientists believe that two asteroids might be fragments of long-lost "planetary embryos" from the early solar system.

Why is Pluto no longer a planet? Discover the real reason behind Pluto’s reclassification as a dwarf planet and the science that led to this change.

The building blocks of life could have been delivered to Ceres by one or more space rocks from the outer asteroid belt.

In August 2006, the International Astronomical Union made the controversial, but correct, decision to demote Pluto from its ...

The organic material found in a few areas on the surface of dwarf planet Ceres is probably of exogenic origin. Impacting ...

Take advantage of a special 6-7 planet alignment from Earth's perspective. Planets 'line up' in the skies over California in ...

While the composition of gas and dust in a molecular cloud is fairly uniform, everything changes once a star begins to form.

The dwarf planet ... reached the inner Solar System only later. For the current study, the researchers looked for previously unknown deposits of organic material on dwarf planet Ceres.

That’s because Pluto was downgraded from a “planet” to a “dwarf planet” in 2016 by ... that there really is a ninth planet in our Solar System. The same year that Pluto was ignominiously ...