Infographic of Star Engulfing a Planet

Astronomers using the Gemini South telescope in Chile, operated by NSF’s NOIRLab, have observed the first compelling evidence of a dying Sun-like star engulfing an exoplanet. For most of its life, a Sun-like star fuses hydrogen into helium in its hot, dense core, which allows the star to push back against the crushing weight of its outer layers. When hydrogen in the core runs out, the star begins fusing helium into carbon and hydrogen fusion migrates to the star’s outer layers, causing them to expand, and changing the Sun-like star into a red giant.

Such a transformation, however, is bad news for any inner-system planets. When the star's surface eventually expands to engulf one of its planets, their interaction would trigger a spectacular outburst of energy and material. This process would also put the brakes on the planet's orbital velocity causing it to plunge into the star.