NASA’s Chandra Observatory Finds Baby Planet Being Eroded by Host Star’s X-Rays.

A very young, Jupiter-sized planet is dramatically shrinking under the intense bombardment of high-energy X-rays from its parent star, according to a new study using NASA’s Chandra X-ray Observatory.

The planet, known as TOI 1227 b, orbits its faint red star at a distance much closer than Mercury is to the Sun. At just 8 million years old—about 1/1,000th the age of our Sun—TOI 1227 b is undergoing a violent transformation, astronomers say.

Chandra data reveals that the planet’s host star is emitting a torrent of X-rays that are relentlessly stripping away TOI 1227 b’s thick atmosphere. Scientists estimate the planet is losing mass equivalent to an entire Earth’s atmosphere every 200 years. At this rate, TOI 1227 b is expected to shrink from a gas giant the size of Jupiter into a small, barren world.

“This is a rare opportunity to observe a planet undergoing rapid and extreme atmospheric loss,” said lead author Attila Varga of the Rochester Institute of Technology. “We’re witnessing planetary evolution in real time.”

An artist’s illustration accompanying the study shows the young planet clinging to its atmosphere as powerful stellar radiation tears material away, forming a blue tail reminiscent of a comet. A smaller inset image displays the X-ray data from Chandra, where the star appears as a purple dot against the blackness of space.

The research team used a combination of methods to estimate the system’s age, including tracking the motion of the star relative to nearby stellar populations and comparing its brightness and temperature to theoretical models of stellar evolution. These methods confirmed TOI 1227 b’s youthful age and offered insight into how extreme radiation shapes planetary development.

Among known exoplanets younger than 50 million years, TOI 1227 b stands out. It has the longest orbital period and orbits the lowest-mass host star in its age group. These unique characteristics, combined with the intense radiation environment, make it a prime target for future studies.

The findings are detailed in a paper accepted for publication in The Astrophysical Journal. The research was led by scientists from the Rochester Institute of Technology, the University of Tübingen in Germany, MIT, and the University of New South Wales Canberra.

NASA’s Marshall Space Flight Center manages the Chandra program, while the Smithsonian Astrophysical Observatory oversees science and flight operations from Massachusetts.