Launched almost exactly 10 years ago, the Kepler Space Telescope has discovered thousands of exoplanets using the transit method — small dips in a star’s brightness as planets cross in front of the star. Because other phenomena can mimic transits, Kepler data reveal planet candidates, but further analysis is required to confirm them as genuine planets.
Kepler-1658 is 50% more massive and three times larger than the Sun. The newly confirmed planet orbits at a distance of only twice the star’s diameter, making it one of the closest-in planets around a more evolved star — one that resembles a future version of our Sun. Standing on the planet, the star would appear 60 times larger in diameter than the Sun as seen from Earth.
Planets orbiting evolved stars similar to Kepler-1658 are rare, and the reason for this absence is poorly understood. The extreme nature of the Kepler-1658 system allows astronomers to place new constraints on the complex physical interactions that can cause planets to spiral into their host stars. The insights gained from Kepler-1658b suggest that this process happens slower than previously thought, and therefore may not be the primary reason for the lack of planets around more evolved stars.
“Kepler-1658 is a perfect example of why a better understanding of host stars of exoplanets is so important.” said Chontos. “It also tells us that there are many treasures left to be found in the Kepler data.”