Researchers have discovered the nearest brown dwarf with a disk that could potentially generate new planets, which could help them learn more about planet formation. The findings were presented Tuesday at a virtual meeting of the American Astronomical Society.
Brown dwarfs are a middle ground between planets and stars. Formed from a gravitational collapse of gas and dust, brown dwarfs stabilize into a mild state, instead of forming a hot nuclear core like stars. They glow relatively dimly, making them hard to spot in the night sky. Some brown dwarfs, like stars, retain a disk of swirling gas from their initial formation.
“We’ve basically found the closest young brown dwarf” with a disk, said study co-author Steven Silverberg, a postdoctoral student in the Massachusetts Institute of Technology’s Kavli Institute for Astrophysics and Space Research. “We’ve found younger brown dwarves with disks [farther away], and closer but older ones that don’t have disks.”
Researchers from MIT and the University of Oklahoma, along with 15 citizen scientists, first discovered the brown dwarf, named W1200-7845, in 2016. At about 332 light years from Earth, it is very close compared with other brown dwarves. It is about 3.7 million years old and part of a moving group of about 30 stars.
“When it’s this close, we consider it to be within the solar neighborhood,” said lead author Maria Schutte, a graduate student at the University of Oklahoma, in MIT News. “That proximity is really important, because brown dwarfs are lower in mass and inherently less bright than other objects like stars. So the closer these objects are to us, the more detail we’ll be able to see.”
Using the crowdsourcing website Disk Detective, funded by NASA and hosted by Zooniverse, citizen scientists study images provided by NASA’s Wide-field Infrared Survey Explorer (WISE) to identify objects that the infrared telescope cannot distinguish. The goal, according to researchers, is to distinguish between galaxies and other astronomical objects with disks that could potentially form planets.
“A group of incredibly dedicated volunteers have learned how to look up objects in standard astronomical catalogs and find more data about them,” Silverberg said.
After citizen scientists provide their findings, researchers dig deeper using more sophisticated methods and telescopes to confirm whether the objects have a disk, and what characteristics the disk may have. In the brown dwarf’s case, the team used the Magellan 6.5-meter telescopes at Las Campanas Observatory in Chile.
Since Disk Detective’s founding in 2014, over 10,000 citizen scientists have contributed to the effort, Silverberg said. Sifting through each image wouldn’t be possible for researchers to do alone, due to the amount of material.
“None of the science that we talked about would happen without citizen science, so it's a credit to the people that take part in the site that have contributed,” Silverberg said.
The team of researchers plans to use other telescopes, such as the Atacama Large Millimeter Array (ALMA) in Chile, to zoom in closer to the brown dwarf in hopes of measuring the disk’s mass and radius, which could tell scientists if planets can form there, and what kind of planets can form.
An updated version of Disk Detective will be available this week for citizen scientists, providing more current images from different telescopes with better resolution, researchers said.
Matt Berg can be reached at firstname.lastname@example.org. Follow him on Twitter @mattberg33.