Astronomers uncover evidence that there could be many more Earth-sized planets than previously thought
June 28, 2021
by Association of Universities for Research in Astronomy (AURA)
Some exoplanet searches could be missing nearly half of the Earth-sized planets around other stars. New findings from a team using the international Gemini Observatory and the WIYN 3.5-meter Telescope at Kitt Peak National Observatory suggest that Earth-sized worlds could be lurking undiscovered in binary star systems, hidden in the glare of their parent stars. As roughly half of all stars are in binary systems, this means that astronomers could be missing many Earth-sized worlds.
Earth-sized planets may be much more common than previously realized. Astronomers working at NASA Ames Research Center have used the twin telescopes of the international Gemini Observatory, a Program of NSF's NOIRLab, to determine that many planet-hosting stars identified by NASA's TESS exoplanet-hunting mission are actually pairs of stars—known as binary stars—where the planets orbit one of the stars in the pair. After examining these binary stars, the team has concluded that Earth-sized planets in many two-star systems might be going unnoticed by transit searches like TESS's, which look for changes in the light from a star when a planet passes in front of it. The light from the second star makes it more difficult to detect the changes in the host star's light when the planet transits.
