Citizen Scientists Discover More Extreme Brown Dwarfs

Brown dwarfs are celestial bodies smaller than the least massive stars but larger than the biggest planets. Backyard Worlds: Planet 9 is a NASA-funded citizen science project that uses data from NASA’s WISE space telescope to search for new neighbors to the Sun, especially brown dwarfs.

In 2020, Backyard Worlds citizen scientists helped discover a new class of bizarre brown dwarfs, referred to as ‘extreme T-type subdwarfs’. These unusual brown dwarfs are ancient members of the Milky Way Galaxy, and can provide unique insights about low mass star formation in the early Universe and the atmospheres of giant exoplanets orbiting old stars.

Now Backyard Worlds citizen scientists are back at it once again in a newly published scientific journal paper! Our volunteers have recently discovered three more brown dwarfs resembling the two previously known extreme T-type subdwarfs, a major step forward in understanding the properties of very cold, ancient brown dwarfs. The new discoveries were identified based on their peculiar colors and very fast motions across the sky. Seven citizen scientists are co-authors of the newly published study.

Artist rendering of the exceptionally fast-moving brown dwarf WISE J1553, discovered by Backyard Worlds: Planet 9 citizen scientists Nikolaj Stevnbak Andersen and David W. Martin. Credit: Image courtesy of William Pendrill.

Thanks to NASA’s ongoing NEOWISE mission, there are still huge amounts of data yet to be explored within the Backyard Worlds web interface. Join in at!


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: