Using NASA's exoplanet-hunting spacecraft TESS (Transiting Exoplanet Survey Satellite) astronomers have discovered an extraordinary quadruple star. The system is the tightest 3+1-star system, a subset of quadruple star systems, yet discovered. Excitingly, the discoverers of this system were also able to determine what its final fate will be.
The system TIC 120362137 consists of a stable and tightly bound inner system of three stars orbiting each other that are orbited by a more distant outer star observing the system from afar. While the outer star is located at around the same distance from the stellar triplet as the distance from Jupiter to the sun, the inner stellar sub-system would fit within the orbit of Mercury, the closest planet to the sun, around our star.
