An exoplanet or extrasolar planet is a planet that orbits a star other than the Sun. The first scientific detection of an exoplanet was in 1988. However, the first confirmed detection came in 1992; since then, and as of 1 April 2017, there have been 3,607 exoplanets discovered in 2,701 planetary systems and 610 multiple planetary systems confirmed.
1- Kepler-186f
was the first rocky planet to be found within the habitable zone – the region around the host star where the temperature is right for liquid water. This planet is also very close in size to Earth. Even though we may not find out what’s going on at the surface of this planet anytime soon, it’s a strong reminder of why new technologies are being developed that will enable scientists to get a closer look at distant worlds.
2- CoRoT 7b
The first super-Earth identified as a rocky exoplanet, this planet proved that worlds like the Earth were indeed possible and that the search for potentially habitable worlds (rocky planets in the habitable zone) might be fruitful.
3- Kepler-22b
A planet in the habitable zone and a possible water-world planet unlike any seen in our solar system.
4- Kepler 10-b
Kepler’s first rocky planet discovery is a scorched, Earth-size world that scientists believe may have a lava ocean on its surface.
5- 55 Cancri e
55 Cancri e is a toasty world that rushes around its star every 18 hours. It orbits so closely – about 25 times closer than Mercury is to our sun – that it is tidally locked with one face forever blisters under the heat of its sun. The planet is proposed to have a rocky core surrounded by a layer of water in a “supercritical” state, where it is both liquid and gas, and then the whole planet is thought to be topped by a blanket of steam.
6- 51 Pegasi b
This giant planet, which is about half the mass of Jupiter and orbits its star every four days, was the first confirmed exoplanet around a sun-like star, a discovery that launched a whole new field of exploration.
7- Kepler-444 system
The oldest known planetary system has five terrestrial-sized planets, all in orbital resonance. This weird group showed that solar systems have formed and lived in our galaxy for nearly its entire existence.
8- PSR B1257+12 system
Discovered in 1992 and 1994, the planets that orbit pulsar PSR B1257+12 are not only the smallest planetary bodies known to exist outside our solar system, they also orbit a neutron star. These weird “pulsar planets” demonstrated that planets exist in all environments in the galaxy – even around the remnants of an exploded star.
9- HD 80606 b
This world has the most eccentric orbit, and as one scientist put it, “wears its heart on its sleeve,” with storms, rotation, atmospheric heating, and a crazy orbit all plainly visible.
10- OGLE-2005-BLG-390
Considered to be the first cold super Earth, this exoplanet began to form a Jupiter-like core of rock and ice, but couldn’t grow fast enough in size. Its final mass is five times that of Earth. The planet’s nickname is Hoth, after a planet from Star War
