TIC 452991707 and TIC 452991693 as a Candidate Sextuple System with Three Eclipsing Binaries

TL;DR

This paper reports the discovery of a rare sextuple star system with three eclipsing binaries, identified in TESS data, where two stars are gravitationally bound and exhibit complex orbital interactions.

Contribution

It presents the identification of a unique sextuple system with three eclipsing binaries, including detailed analysis of their periods and potential orbital dynamics, based on TESS and archival data.

Findings

Three distinct eclipsing periods identified: 1.46155 d, 1.77418 d, 1.03989 d.

The system includes a gravitationally bound pair separated by about 16 arcseconds.

Inner pairs A and B likely orbit each other over a period of a few years.

Abstract

We present the discovery of a rare system detected in the TESS data showing three different eclipsing-like signals. TIC 452991707 and TIC 452991693 seem to be the second such system on the sky, whose two components separated about 16" are gravitationally bounded, or comprise a co-moving pair. The three periods detected from the TESS data are: PA=1.46155 d, PB=1.77418 d, and PC=1.03989 d, respectively. The A and B periods belong to TIC 452991707, while the C comes from the component TIC 452991693. The pair A shows the deepest eclipses, and its orbit is very slightly eccentric. The third period C has lowest amplitude (eclipsing or ellipsoidal nature), but originates from TIC 452991693, which is connected to A+B because both visual components share similar proper motion and distance. Long-term collection of data from older photometry from various surveys also shows that the two inner pairs A and B orbit around their barycenter. Its period is probably of a few years, but for a final derivation of its orbital parameters one needs more up-to-date data. Hence, we call for new observations of this amazing system.