EQ Pegasi


EQ Pegasi is a nearby binary system of two red dwarfs. Both components are flare stars, with spectral types of M4Ve and M6Ve respectively, and a current separation between the components of 5.8 arcseconds. The system is at a distance of 20.4 light-years, and is 950 million years old. The primary star is orbited by one known exoplanet.

Discovery

EQ Pegasi was first noticed to be a binary star by Carl A. Wirtanen who in the course of a systematic survey of the McCormick Observatory photographic plates for M-type dwarfs, detected a companion about two magnitudes fainter at a separation of 3.5 arcseconds.
Both components were also thought to be single-lined spectroscopic binaries, with faint companions that have not been resolved in orbits of a few years, but this is no longer thought to be the case. A 2021 study of nearby stars states that "the spectroscopic binarity classification is almost certainly due to activity".

Planetary system

In 2022, a Jovian planet was discovered in orbit around the system's primary star via radio astrometry. Along with the planet around TVLM 513-46546, this is the first confirmed exoplanet discovered entirely using astrometry.

In culture

In 1998, it was the basis of a hoax, as a telecommunications company claimed it had discovered "alien" signals originating from the star.