Physics/Astronomy/Planets

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A planet is an object orbting a star in space. The Solar System is known to have 8 planets. Pluto is no longer a planet.

After 2006, a planet is something that is in orbit around the Sun, has enough mass so that it has a nearly round shape, and has "cleared the neighbourhood" around its orbit. 'Clearing the neighbourhood' means that the

planet must have enough gravity to pull the asteroids towards the planet or change the path asteroid so that the asteroid do not remain in or around the orbit of planet.

List of Planets in our Solar System

MESSENGER first photo of unseen side of mercury.jpg
Venus globe.jpg
The Earth seen from Apollo 17.jpg
Mars Hubble.jpg
Jupiter by Cassini-Huygens.jpg
Saturn from Cassini Orbiter (2004-10-06).jpg
Neptune.jpg