The Kepler mission has spotted thousands of exoplanets since 2014, with 30 planets less than twice the size of Earth now orbiting the habitable zones of their stars.
Launched at Cape Canaveral on March 7, 2009, the Kepler telescope has helped search for planets outside the solar system.
He captured his latest image on September 25, 2018 and ran out of fuel five days later.
When launched, it weighed 2,320 lbs (1,052 kg) and is 15.4 feet long by 8.9 feet wide (4.7 m × 2.7 m).
The satellite generally searches for “Earth-like” planets, which means they are rocky and orbiting that orbit in the habitable zone or “Goldilocks” of a star.
In total, Kepler found around 5,000 unconfirmed “candidate” exoplanets, along with 2,500 other “confirmed” exoplanets that scientists have since demonstrated to be real.
Kepler is currently on a “K2” mission to discover more exoplanets.
K2 is the second mission of the spacecraft and was implemented out of necessity out of desire, because two reaction wheels on the spacecraft failed.
These wheels control the direction and altitude of the spacecraft and help steer it in the right direction.
The modified mission examines exoplanets around dark red dwarf stars.
While the planet has found thousands of exoplanets during its eight-year mission, five in particular have come out.
Kepler-452b, nicknamed “Earth 2.0”, shares many characteristics with our planet although it is 1400 light years from us. It was found by NASA’s Kepler telescope in 2014
1) “Earth 2.0”
In 2014, the telescope made one of its biggest discoveries by locating the Kepler-452b exoplanet, nicknamed “Earth 2.0”.
The object shares many characteristics with our planet although it is 1400 light years from us.
It has an orbit of similar size to Earth, receives roughly the same amount of sunlight and has the same length of year.
Experts still don’t know if the planet is home to life, but say that if plants were transferred there, they would likely survive.
2) The first planet found in orbit around two stars
Kepler found a planet in orbit around two stars, known as the binary star system, in 2011.
The system, known as the Kepler-16b, is about 200 light years from Earth.
Experts have compared the system to the famous “double sunset” illustrated on Luke Skywalker’s home planet, Tatooine, in “Star Wars: A New Hope”.
3) Find the first habitable planet outside the solar system
Scientists discovered Kepler-22b in 2011, the first habitable planet found by astronomers outside the solar system.
The habitable super-Earth appears to be a large rocky planet with a surface temperature of about 72 ° F (22 ° C), similar to a spring day on Earth.
4) Discover a “super-Earth”
The telescope found its first “super-Earth” in April 2017, a huge planet called LHS 1140b.
It orbits a red dwarf star about 40 million light years away, and scientists believe it contains giant oceans of magma.
5) Find the star system ‘Trappist-1’
The Trappist-1 star system, which hosts a record number of seven Earth-like planets, was one of the biggest discoveries of 2017.
Each of the planets, which orbits a dwarf star just 39 million light-years away, probably contains water on its surface.
Three of the planets have such good conditions that scientists say that life may have already evolved with them.
Kepler spotted the system in 2016, but scientists revealed the discovery in a series of articles published in February of this year.
Kepler is a telescope with an incredibly sensitive instrument known as a photometer that detects the slightest changes in light emitted by stars
How does Kepler discover the planets?
The telescope has an incredibly sensitive instrument known as a photometer that detects the slightest changes in light emitted by stars.
It tracks 100,000 stars simultaneously, looking for revealing drops in light intensity that indicate a planet in orbit passing between the satellite and its distant target.
When a planet passes in front of a star seen from Earth, the event is called “transit”.
Tiny dips in the brightness of a star during transit can help scientists determine the orbit and size of the planet, as well as the size of the star.
Based on these calculations, scientists can determine whether the planet is in the star’s “habitable zone”, and therefore whether it could host the conditions for the growth of extraterrestrial life.
Kepler was the first spacecraft to study the planets in our own galaxy, and over the years, his observations have confirmed the existence of more than 2,600 exoplanets – many of which could be key targets in the search for extraterrestrial life.