A new Earth-sized exoplanet has been discovered. Kepler-1649 c has a radius of 1.06 times earth. And just like the name suggests the discovery comes from the Kepler data. The Kepler telescope was retired on October 2018 30, 2018. The planet was originally analyzed by Kepler's Robovetter algorithm. Robovetter is open-source software that automates the process to distinguish between likely planet candidates and false positives in the Kepler dataset.
Image Credit: NASA/Ames Research Center/Daniel Rutter
Robovetter labeled Kepler-1649 c as a false positive. A computer algorithm could make mistakes when it comes to analyzing tricky signals. Therefore a group of scientists called the Kepler False Positive Working Group has the mission to manually review and confirm all those false positives. They discovered that Kepler-1649 c is not a false positive and published these findings in April 2020.
Earlier in 2017 an earth size planet Kepler-1649 b was discovered around the star the planet orbits closer to the star. The interesting thing is how these two exoplanets are interacting with each other when the first planet makes 4 revolutions around its star the second one makes 9. This makes it a very stable system. Kepler-1649 c is in the habitable zone of its star and could have the same temperature as Earth while Kepler-1649 b could be more similar to Venus.
The star Kepler-1649 is 300 light-years away and is a red dwarf star with 0.22 times the mass of our sun. The problem with red dwarfs is that they could have a very high stellar activity that gives violent flares, no flares have been observed around Kepler-1649 so far. This is a very interesting discovery that confirms Earth-size planets in the habitable zone are very common around red dwarf stars. And it increases the possibility that one will have the same condition as Earth