TIC 168789840: A Sextuply-Eclipsing Sextuple Star System

Abstract

We report the discovery of a sextuply-eclipsing sextuple star system from TESS data, TIC 168789840, also known as TYC 7037-89-1, the first known sextuple system consisting of three eclipsing binaries. The target was observed in Sectors 4 and 5 during Cycle 1, with lightcurves extracted from TESS Full Frame Image data. It was also previously observed by the WASP survey and ASAS-SN. The system consists of three gravitationally-bound eclipsing binaries in a hierarchical structure of an inner quadruple system with an outer binary subsystem. Follow-up observations from several different observatories were conducted as a means of determining additional parameters. The system was resolved by speckle interferometry with a 0."42 separation between the inner quadruple and outer binary, inferring an estimated outer period of ~2 kyr. It was determined that the fainter of the two resolved components is an 8.217 day eclipsing binary, which orbits the inner quadruple that contains two eclipsing binaries with periods of 1.570 days and 1.306 days. MCMC analysis of the stellar parameters has shown that the three binaries of TIC 168789840 are "triplets", as each binary is quite similar to the others in terms of mass, radius, and Teff. As a consequence of its rare composition, structure, and orientation, this object can provide important new insight into the formation, dynamics, and evolution of multiple star systems. Future observations could reveal if the intermediate and outer orbital planes are all aligned with the planes of the three inner eclipsing binaries.

References in corpus (13)

• Array Programming with NumPy
• Modules for Experiments in Stellar Astrophysics (MESA)
• The Transiting Exoplanet Survey Satellite
• Modules for Experiments in Stellar Astrophysics (MESA): Pulsating Variable Stars, Rotation, Convective Boundaries, and Energy Conservation
• The All-Sky Automated Survey for Supernovae (ASAS-SN) Light Curve Server v1.0
• The statistical properties of stars and their dependence on metallicity
• Discovery and Vetting of Exoplanets I: Benchmarking K2 Vetting Tools
• The single-sided pulsator CO~Camelopardalis
• EPIC 220204960: A Quadruple Star System Containing Two Strongly Interacting Eclipsing Binaries
• The formation of higher-order hierarchical systems in star clusters
• Doubly eclipsing systems
• The orbits of the quadruple star system 88 Tau A from PHASES differential astrometry and radial velocity
• FRAM telescopes and their measurements of aerosol content at the Pierre Auger Observatory and at future sites of the Cherenkov Telescope Array

Cited by in corpus (1)

• BG Ind: the nearest doubly eclipsing, compact hierarchical quadruple system