Planetary engulfment in the Hertzsprung-Russell Diagram. Optical and X-ray transients from planet-star mergers. The occurrence and architecture of exoplanetary systems. Future Galactic plane surveys should routinely identify these, showing the demographics of planetary engulfment and the ultimate fate of planets in the inner Solar System. We estimate the Galactic rate of such subluminous red novae to be roughly between 0.1 and several per year. Its exceptionally low optical luminosity (approximately 10 35 erg s −1) and radiated energy (approximately 6.5 × 10 41 erg) point to the engulfment of a planet of fewer than roughly ten Jupiter masses by its Sun-like host star. The resulting light curve and spectra share striking similarities with those of red novae 6, 7-a class of eruptions now confirmed 8 to arise from mergers of binary stars.

Here we report observations of ZTF SLRN-2020, a short-lived optical outburst in the Galactic disk accompanied by bright and long-lived infrared emission. However, this phase has never been directly observed.

Stars expand as they evolve and thus we expect their close planetary companions to be engulfed, possibly powering luminous mass ejections from the host star 3, 4, 5. Planets with short orbital periods (roughly under 10 days) are common around stars like the Sun 1, 2. Nature volume 617, pages 55–60 ( 2023) Cite this article

An infrared transient from a star engulfing a planet

Books like the sun is also a star