Reassessment of Earth-like planet candidates with a decoy planet search

What is it about?

We present a new way to check how likely a Kepler “planet” really is. Instead of altering the data, we run a companion search with a decoy template that can’t match real planets but does pick up the same kinds of false alarms. Comparing the real search to this decoy search lets us assign a star-by-star false-alarm probability. Re-examining 47 previously proposed Earth-size and super-Earth candidates in the habitable zone, we find 29 with <1% chance of being false alarms, including Kepler-452 b, a near-Earth-size world on a 384-day orbit around a Sun-like star.

Featured Image

Photo by NASA Hubble Space Telescope on Unsplash

Photo by NASA Hubble Space Telescope on Unsplash

Why is it important?

The new method provides reliable means to estimate the reliability of exoplanet candidates, which is crucial to make inferences from the exoplanet survey datasets such as Kepler, TESS and the future missions. It enables reliable calculations of the occurrence of planets at the detection limit, such as Earth-like planets in the habitable zone.