Astronomers Spot a Rare Quadruple Star System in the Milky Way, Shedding Light on Mysterious Brown Dwarfs

The discovery can help astronomers better understand these little-known objects nicknamed “failed stars”

Sara Hashemi - Daily Correspondent

August 29, 2025



An artist's depiction of the newly discovered "quadruple system" within the Milky Way. In it, two brown dwarfs orbit each other at the right, and together, they orbit a pair of red dwarf stars at the left. Jiaxin Zhong / Zenghua Zhang


Astronomers have discovered a first-of-its-kind quadruple star system in our own Milky Way, a surprising find that could help scientists better understand mysterious objects called brown dwarfs.

Also known as “failed stars,” brown dwarfs form like normal stars but fail to gain enough mass to properly fuse hydrogen. These objects—something between a planet and a star—are notoriously difficult to study. They’re small, cold and faint, making them hard to detect. And determining a brown dwarf’s age also poses a challenge. That’s because, unlike stars, brown dwarfs continuously cool throughout their lifespan, so their characteristics are constantly changing.

To find these strange objects, astronomers might look for brown dwarfs when they’re young and still burning brightly, or seek out ones that are relatively close to us.

Zenghua Zhang, an astronomer at Nanjing University in China, and his team were initially searching for brown dwarfs by seeking out their bright stellar companions. The scientists sifted through data from the European Space Agency’s Gaia telescope and NASA’s Wide-field Infrared Survey Explorer (WISE) and were rewarded when they identified a brown dwarf orbiting a bright star.

More:
https://www.smithsonianmag.com/smart-news/astronomers-spot-a-rare-quadruple-star-system-in-the-milky-way-shedding-light-on-mysterious-brown-dwarfs-180987241/