This artist’s concept shows a brown dwarf, a ball of gas not massive enough to power itself the way stars do. Despite their name, brown dwarfs would appear magenta or orange-red to the human eye if seen close up. Credit: CC byWilliam Pendrill
With the help of citizen scientists, astronomers have discovered two highly unusual brown dwarfs, balls of gas that are not massive enough to power themselves the way stars do.
Participants in the NASA-funded Backyard Worlds: Planet 9 project helped lead scientists to these bizarre objects, using data from NASA’s Near-Earth Object Wide-Field Infrared Survey Explorer (NEOWISE) satellite along with all-sky observations collected between 2009 and 2011 under its previous moniker, WISE. Backyard Worlds: Planet 9 is an example of “citizen science,” a collaboration between professional scientists and members of the public.
Scientists call the newly discovered objects “the first extreme T-type subdwarfs.” They weigh about 75 times the mass of Jupiter and clock in at roughly 10 billion years old. These two objects are the most planetlike brown dwarfs yet seen among the Milky Way’s oldest population of stars.