An aging star caught swallowing Jupiter-size planet; Will Earth suffer the same fate?

Astronomers have found the first direct evidence of an aging star engulfing a Jupiter-size planet. This star depleted its core's fuel and consequently started to expand in size, causing the distance between it and its neighbouring planet to shrink, ultimately consuming it entirely.

In approximately 5 billion years from now, our life-giving star, the Sun, will experience a similar aging process, potentially reaching up to 100 times its current diameter and transforming into a red giant. In the course of this expansion, it is expected that Mercury and Venus will be assimilated, and there is a possibility that Earth may also be engulfed.

"This type of event has been predicted for decades, but until now we have never actually observed how this process plays out," said Kishalay De, an astronomer at the Massachusetts Institute of Technology in Cambridge and the study's lead author.

The event was observed using multiple ground-based observatories and NASA's NEOWISE (Near-Earth Object Wide Field Infrared Survey Explorer) spacecraft which scans the entire sky in infrared light. The hungry star is at the beginning of the final phase of its life, called the red giant phase, which can last more than 100,000 years.

Recent observations show that after devouring the planet, the star temporarily grew in brightness and size and eventually returned to how it was before the merger.

We've long thought that, at the end of their lives, stars like our Sun swell up to 100 times their former diameter and consume surrounding planets. Now, we've seen it. 15,000 light-years away, a hungry star consumed a nearby planet. https://t.co/2XcfC7djIM pic.twitter.com/Ym6GJsMn6Y

— NASA Exoplanets (@NASAExoplanets) May 3, 2023

Theorists believe that a majority of mid-sized stars will eventually evolve into red giants, and a few of them will consume nearby planets each year in our galaxy. The new observation of a star consuming a nearby planet could serve as a useful reference for astronomers, providing them with a model of what similar events might look like.