A schematic showing the relative positions of three binary stars making up a rare sextuple system. Two of the binaries, shown as A and C in this diagram, orbit each other every four years while the third binary, B, is much farther away, taking about 2,000 years to complete an orbit. Image: Goddard Space Flight Center
Astronomers studying data from NASA’s Transiting Exoplanet Survey Satellite, or TESS, have found a remarkable sextuple star system featuring three gravitationally bound eclipsing binaries.
The system, known as TYC 7037-89-1, is located about 1,900 light years from Earth in the constellation Eridanus. It is the first known example of six stars making up a trio of eclipsing binaries, known as A, B and C.
The primary stars in all three binaries undergo periodic eclipses, passing in front of each other as viewed by TESS. The changing light curves show all three primary stars are slightly more massive than the sun, but about as hot. The secondary stars are roughly half the size the Sun.
The two stars making up the A binary orbit each other every 1.3 days while the stars in binary C orbit each other every 1.6 days. The A and C ...