Kepler's First Exoplanet Candidate Discovered A Decade Ago Finally Confirmed

The Kepler space telescope has a new feather in its cap as its very first exoplanet candidate discovered a decade ago has finally been confirmed. The exoplanet is called Kepler-1658b, and it had a long road to confirmation. Part of the delay was due to initial estimates of the size of the planet's host star being off.

With the size of the host star being off, the size of Kepler-1658b was "vastly underestimated." Initially, the planet was marked as a false positive because scientists thought the data didn't point to the existence of a planet. New software was developed and used to refine the data and reclassify it, Kepler-1658b was again a possible planet.

A team from the University of Hawaii including a grad student in Astronomy called Ashley Chontos went through the data in 2017 looking for targets to reanalyze, Kepler-1658b was among them. Chontos said the new software analysis showed the host star was three times larger than previously believed, making the planets three times larger than previous estimates.

The new classification meant that the planet is now categorized as a hot Jupiter. The team then reached out to other scientists to gather spectroscopic data that confirmed Kepler-1658b was a planet. The planet orbits its parent star once every 3.85 Earth days.

The host star of the exoplanet is said to be a future version of our Sun. Kepler-1658b is so close to its host star that NASA says the star would appear 60-times larger in diameter than the sun viewed from Earth.