Astronomers observed a sun‑like star expanding dramatically enough to engulf a nearby planet. This dramatic event has been reported by AURA, offering a vivid window into late‑life stellar activity.
Modern astrophysical data show that in their twilight years, stars similar to the Sun swell into red giants. As their cores exhaust fuel, their outer layers puff out, increasing the diameter many times over. In extreme cases, the growing star can encompass the orbits of inner planets, reshaping the architecture of the entire system.
Researchers led by Ryan Lau and colleagues verified this behavior through observations with the Gemini South telescope. Distinguishing a planetary engulfment from other high-energy events such as solar flares or coronal mass ejections requires exceptional resolution, and careful tracking of how the flare evolves over time.
The engulfment episode persisted for roughly 100 days. The light curve shape and the properties of the ejected material enabled scientists to estimate both the mass of the host star and the swallowed planet. The expelled matter comprised about 33 Earth masses of hydrogen and roughly 0.33 Earth masses of dust, painting a detailed picture of the interaction at play.
From these measurements, researchers inferred that the parent star weighs in at roughly 0.8 to 1.5 solar masses, while the absorbed planet likely falls in the range of 1 to 10 Jupiter masses. These figures help map the dynamics of violent star–planet encounters and the fate of close‑in worlds when stellar envelopes expand.
The implications stretch beyond a single system. Based on current models, Earth and the rest of our solar system face a similarly dramatic end in about 5 billion years as the Sun evolves toward a red giant phase.
Beyond the spectacle of a star consuming a planet, these observations contribute to a broader understanding of planetary survivability in aging systems. They illuminate how stellar winds, heat, and tidal forces interact with nearby worlds, ultimately deciding which planets endure and which are lost to the star’s expanding embrace.
In the broader scientific narrative, such events also serve as natural laboratories. They reveal how stellar material is redistributed during late stages of evolution and offer clues about the chemical fingerprints left behind in the circumstellar environment. This in turn informs theories about planetary formation, migration, and the long‑term evolution of planetary systems across the galaxy. Researchers continue to refine their models by comparing observed light curves with simulations, seeking to reconcile theory with what telescopes actually record in real time, sometimes using multi‑instrument campaigns to capture different facets of the same event.