Known as exoplanets, the first evidence of one was noted as far back as 1917 but a lack of knowledge about space meant the find was not noted as such and forgotten about for nearly a hundred years. The scientific definition was agreed in 1988 but the first confirmed spot did not occur until 1992. There are currently over 4,000 confirmed exoplanets in 3,000 different solar systems.
NASA has just weeks ago discovered exoplanet L 98-59 tweeting: “The tiniest exoplanet!
“Our NASA Transiting Exoplanet Survey Satellite mission discovered a world that’s smaller than Earth and larger than Mars, orbiting a bright, cool, nearby star about 35 light-years away.”
The closest to Earth is Proxima Centauri b, located some 4.2 light years from her home, orbiting Proxima Centauri, the closest star to our Sun.
As Cnet reported, finds after 1992 remained small until the Kepler Space Telescope was bought into action before its recent retirement.
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NASA have now created a video visualising the discovery of the exoplanets.
Two telecopies European Characterising Exoplanets Satellite (CHEOPS) and the NASA James Webb Telescope are set to launch into action at the end of 2019 and 2021 respectively aimed at spotting exoplanets and working out if they can support life.
The exoplanets are all very far off with light taking 4.2 years to travel from Proxima Centauri b to Earth despite travelling at an unimaginable speed of 300,000km/s (186,000mi/s).
This means light can travel a metre (1.1yards) in an insanely small 1/299792458th of a second.
As well as exoplanets, there is another category of planet called rogue planets.
These planets do not orbit a star but instead orbit the centre of the galaxy.
They are ejected from the planetary system or never gravitonally pulled in by a star, the Milky Way may have billions of these planets.
It has been suggested some of these celestial objects are formed in the same way as stars.