Establish the nature of the TIC 184739529 companion

Establish whether the TIC 184739529 companion is a planet, brown dwarf, stellar companion, or blended eclipsing-binary signal.

Background

TIC 184739529 has a coherent transit-like signal, but its approximately 4.4 per cent depth and nominal radius of about 13.7 Earth radii place the companion near the boundary between giant planets, brown dwarfs, and low-mass stars. Its elevated Gaia RUWE of 1.98 and nearby sources within the TESS aperture further raise concerns about unresolved multiplicity or contamination.

Although no statistically significant secondary eclipse or odd-even depth difference is detected, these diagnostics do not exclude a stellar or blended origin. Additional observations, especially high-resolution imaging and precision radial-velocity monitoring, are needed to determine the companion's physical nature.

References

Taken together, the large transit depth and correspondingly large inferred companion radius, elevated RUWE, and aperture-contamination risk make TIC~184739529 a high-risk candidate. We therefore regard it as a giant-planet-sized companion of uncertain nature, with brown-dwarf, stellar-companion, and blended eclipsing-binary scenarios remaining viable, rather than as a secure planet candidate.

— A chemo-dynamical search for planet-candidate hosts of possible extragalactic origin  (2608.13895 - Tiancheng et al., 14 Aug 2026) in Section 3.2, False-positive Vetting of the Planet Candidates