Baby exoplanet caught shrinking under host star’s rays by NASA’s Chandra

An artist’s illustration of a Jupiter-sized planet closely orbiting a faint red star. An inset image, showing the star in X-ray light from Chandra, is superimposed on top of the illustration at our upper left corner. (Image: NASA)

Far away in space, a baby world is withering fast. Astronomers say it's shrinking, shedding its thick gas shell. The planet, named TOI 1227 b, faces a harsh future. It orbits a red dwarf about 330 light-years from Earth.

This young planet is just 8 million years old today. That’s nearly a thousand times younger than our Earth. But unlike Earth, it sits dangerously close to its parent star.

A Planet Under Fire
NASA's Chandra X-ray Observatory has revealed troubling details. X-rays from the host star hit the planet directly. These rays are stripping away its thick atmosphere fast. Every 200 years, it loses Earth’s atmosphere in mass.

The star, known as TOI 1227, is small and cool. But in X-rays, it’s much brighter than our Sun. Its powerful radiation keeps tearing the baby planet apart.

At first, the planet was nearly the size of Jupiter. But its mass is more like Neptune, astronomers believe. That massive, inflated size won’t last for long.

No Hope for Life
Researchers believe TOI 1227 b is not habitable. It lies far too close to its searing star. No water or life could survive in such heat.

In time, the planet could shrink to one-tenth its size. Over a billion years, it may lose two Earth masses. That’s a dramatic change for any young planet to face.

Experts used motion data to confirm the planet's age. They matched star movement with known stellar age groups. They also checked brightness and temperature models of stars.

Among all known exoplanets under 50 million years old, TOI 1227 b has the longest year. Its host star is also among the smallest found so far.

The study was led by Attila Varga at RIT. Other scientists from Germany and the US joined the work. Their paper will soon appear in The Astrophysical Journal.

NASA’s Marshall Space Flight Centre runs the Chandra mission. Operations are handled by teams in Massachusetts.