Planet V is a hypothetical fifth terrestrial planet posited by NASA scientists John Chambers and Jack J. Lissauer to have once existed between Mars and...

fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than 2.5 times that of all the other planets in the...

Following the discovery of the planet Neptune in 1846, there was considerable speculation that another planet might exist beyond its orbit. The search...

A classical planet is an astronomical object that is visible to the naked eye and moves across the sky and its backdrop of fixed stars (the common stars...

has eight planets by the most restrictive definition of the term: the terrestrial planets Mercury, Venus, Earth, and Mars, and the giant planets Jupiter...

Jupiter have been counted as the fifth planet from the Sun. There are three main ideas regarding hypothetical planets between Mars and Jupiter. During the...

terrestrial planet, Planet V, had a mass less than half of Mars and originally orbited between Mars and the asteroid belt. Planet V's orbit became unstable...

Planet of the Apes is a science fiction media franchise consisting of films, books, television series, comics, and other media about a post-apocalyptic...

Φαέθων, romanized: Phaéthōn, pronounced [pʰa.é.tʰɔːn]) was the hypothetical planet hypothesized by the Titius–Bode law to have existed between the orbits of...

Earth is the third planet from the Sun and the only astronomical object known to harbor life. This is enabled by Earth being an ocean world, the only one...