Looking for Earth 2.0 in Binary Systems

A new NASA Small Explorer mission called Searching for Habitable Exoplanets with Relative Astrometry (SHERA) aims to find Earth-sized planets in multi-star systems using astrometry. The mission uses binary star systems as reference points to detect small movements caused by exoplanets. It is expected to find up to four small, habitable zone planets across its target stars. The mission is designed to help the Habitable Worlds Observatory (HWO) by providing astrometric data to complement ground-based radial velocity measurements.

• SHERA will focus on bright, closely separated binary pairs of stars.
• It uses a diffractive pupil created by electron-beam lithography to measure optical distortions and correct for stellar activity.
• The mission is expected to find around four small, habitable zone planets across its target stars.
• It will test whether close-in binaries suppress planet formation at temperature distances.
• The SHERA team has identified 7 nearby binary systems within 17 parsecs of Earth.

The mission is a stepped-up version of a TOLIMAN 16U CubeSat originally designed to target Alpha Centauri. It is relatively inexpensive and could help HWO reduce the time needed to characterize planets around those stars. HWO is planning to launch late next decade or early 2040s, so the use case may not be valid in the near future. The mission is not yet officially adopted as a NASA mission, and its funding status is unclear.

AI-generated summary of the original article — see the source for the full story.