Planets

For an astronomical body to be classed as a planet it much adhere to the following criterion: it must be in orbit around the Sun, it must be massive enough to reach hydrostatic equilibrium and form a rounded shape and lastly it must have cleared the neighbouring region around its orbit of other large bodies. Our Solar System has five dwarf planets and seven planets. In order of increasing distance from the Sun the planets are: Mercury, Venus, Mars, Earth, Jupiter, Saturn and Uranus, some, but not all, of which have moons.

Groundbreaking study could reveal secrets of how planets are born

The discovery could reveal in greater detail where another planet like Earth is forming.
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Could an asteroid impact ever change Earth’s orbit?

The impact an asteroid could have on Earth depends on many things including velocity, angle and geology.
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Interesting facts, figures and fun questions about the Red Planet

Join us on a journey to the fourth planet from the Sun with amazing facts, incredible images and vital information about Mars.
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Will planet Nibiru crash into Earth? A scientist explains

Nibiru (also known as Planet Nine or Planet X) is prophesied to collide with our planet and destroy all of humanity, but is its existence pseudoscience or is there any proof?
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The Sun: Everything you need to know

The Sun is at the heart of our Solar System, and accounts for over 99 per cent of the total mass.
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Dancing planets: How can I see Venus, Saturn and Mars this week?

Take advantage of the clear skies and look out for the three planets as they come into view.
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Why doesn’t Earth have rings?

Although Earth doesn't have a ring system today, it may have had one in the past.
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20 of the most amazing moons in the Solar System

There are 174 known moons out there, spinning around the celestial bodies of our Solar System, so we’ve decided to pick out our favourites.
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Would happen if two gas planets collided?

Astrophysicist Dr Alastair Gunn explains the outcome of celestial collisions – and what this tells us about our own Solar System.
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Nearby star's death will cause a chaotic game of planet pinball

Astronomers have predicted that the transformation of a star into a white dwarf will send its planets bouncing off each other’s gravity.
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Can a planet orbit backwards compared to the other planets in a solar system?

Asked by: Paul Layfield
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How can we tell that a meteorite has come from a particular planet?

Asked by: Rodney Minns, Liphook, Hampshire
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