NASA first published the image on February 23, 2026. As the space agency explains, it shows a bubble called the astrosphere surrounding the star. Winds from the star's surface inflate this bubble and fill it with hot gas, which expands into much cooler galactic gas and dust.
The Sun also has a similar bubble around it, which scientists call the heliosphere, created by the solar wind. It extends far beyond the planets of the solar system and protects the Earth from cosmic radiation.
This is the first image of the astrosphere taken by astronomers around a star like the Sun. It exhibits a somewhat extended emission, rather than a single point of light, as seen in other similar stars.
“We have been studying the astrosphere of our Sun for decades, but we cannot see it from the outside,” quotes NASA's Cary Lisse of Johns Hopkins University in Baltimore, who led the study. He said Chandra's new findings on the astrosphere of a similar star provide clues about the shape of the Sun's astrosphere and how it has changed over billions of years as the Sun evolves and moves through the galaxy.
The star is called HD 61005 and is relatively close – about 120 light years from Earth. It has about the same mass and temperature as the Sun, but is much younger—its age is about 100 million years, while its age is about 5 billion years.
Because of its young age, HD 61005 experiences much stronger particle winds from its surface. It is about three times faster and about 25 times denser than the solar wind. This enhances the process of bubble formation in the astrosphere and mimics the behavior of the Sun several billion years ago.
