It is believed that it might be an icy or gas planet, around seven times the size of Earth. This would make it much bigger than Pluto, which is smaller than the planets we know. The idea of Planet ...

Astronomers believe Planet Nine might be 5-7 times Earth’s size. It could orbit the sun 200 times farther than Earth. A single orbit might take 10,000 to 20,000 years. Read Also: 'Inspired by ...

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

Ever since NASA's New Horizons sent back the first-ever photos of Pluto in 2015, the dwarf planet's mysterious heart ... roughly the size of Arizona from north to south. Pluto was discovered ...

In 1992 astronomers reported the first planet-size masses around a dead star, the pulsar PSR1257+12, which sits 2,000 light-years away. Three years later came news of the first known exoplanet ...