Astronomers "found" a new potentially habitable Earth-sized exo-planet 300 light-years away. Between 2009 to 2018, the Kepler space telescope owned by NASA found 2,681 exoplanets. Out of all of them, this exo-planet has the nearest comparable size with Earth, along with a possibly similar temperature, according to a recent study published in Astrophysical Journal Letters last Wednesday.
Exoplanets are the term used for planets that orbit stars outside our solar system. The study team uncovered this planet from Kepler's archival data. It used to be classified as a false positive. Even is Kepler has been retired since 2018, its data can still be useful in future "discoveries." NASA is currently using the Transiting Exoplanet Survey Satellite or TESS as its planet-hunting satellite.
The exoplanet is designated as Kepler-1649c. It is 1.06 times bigger than the Earth, and it receives around 75% light that Earth receives from our sun. It is, therefore, possible that its surface temperature may be comparable to ours.
The exoplanet is located within the so-called 'habitable zone' of the star it is orbiting. It is situated in the distance where water can exist as a liquid on its surface, another indicator that it supports or may be able to support life.
Kepler-1649c, however, is orbiting a red dwarf star, which is cooler and smaller than our sun. Exoplanets that orbit such stars are commonly found in the galaxy.
One complete orbit of the planet takes 19.5 days. It may thus experience radiation flares, which may threaten potential life. No flares have so far been observed.
Researchers know of another planet that has a similar size, which is orbiting the star at a closer distance, much like our own Venus.
NASA Science Mission Directorate associate administrator Thomas Zurbuchen said that the distant world gives hope of another Earth out there. He added that Kepler and TESS would yield more amazing discoveries.
This exoplanet is the latest Earth-like find among many others, such as the TRAPPIST-1f located 39 light-years away. Exoplanets such as TOI 700d and TRAPPIST-1D are found to have similar temperature as Kepler-1649c.
But Kepler-1649c is the most interesting candidate exoplanet yet. It was initially overlooked as a potential second Earth candidate because an algorithm put it under the false-positive category. The Kepler False Positive Working Group researchers who analyze false positives reconsidered it.
The University of Texas, Austin researcher, and study author Andrew Vanderburg said that among the planets that they have mislabeled and recovered, Kepler-1649c is especially exciting also
because of the way it could interact with its neighboring planet. They believe that there may be a third exoplanet that they have not yet detected. Their suspicion is based on the orbital resonance of the first two planets, which means that their orbits are lining up in a neat stable ratio. They found that for every nine orbits of Kepler-1649c, the closest and first planet has four orbits. Another planet may thus exist in between them.
Vandenburg says that their data suggests that Earth-like exoplanets are commonly found around red dwarfs, With such stars being present almost everywhere in the galaxy, there is a larger chance that one may be similar enough to our Earth.