NSF–DOE Rubin Observatory will detect thousands of elusive brown dwarfs, unlocking Milky Way mysteries

Too big to be planets but too small to be stars, distant brown dwarfs are a key ingredient for understanding the history of the Milky Way. These elusive objects have existed since the early universe and have remained relatively unchanged.

Anticipated to begin operations in 2025, NSF-DOE Vera C. Rubin Observatory’s 10-year Legacy Survey of Space and Time will detect previously hidden brown dwarfs in the halo of the Milky Way, revealing the processes that shaped this galaxy.


This illustration depicts the population of brown dwarfs in and around the Milky Way that could be detected by NSF-DOE Rubin Observatory. Too big to be planets and too small to be stars, these objects have remained relatively unchanged since they formed in the early Universe. Rubin Observatory’s ten-year Legacy Survey of Space and Time will detect thousands of previously-unseen, faint brown dwarfs, vastly increasing the numbers of these ancient relics that scientists have been able to study thus far, and unlocking clues to the Milky Way’s formation and evolution.
This illustration depicts the population of brown dwarfs in and around the Milky Way that could be detected by NSF-DOE Rubin Observatory. Too big to be planets and too small to be stars, these objects have remained relatively unchanged since they formed in the early Universe. Rubin Observatory’s ten-year Legacy Survey of Space and Time will detect thousands of previously-unseen, faint brown dwarfs, vastly increasing the numbers of these ancient relics that scientists have been able to study thus far, and unlocking clues to the Milky Way’s formation and evolution.

This illustration depicts the population of brown dwarfs in and around the Milky Way that could be detected by NSF-DOE Rubin Observatory. Too big to be planets and too small to be stars, these objects have remained relatively unchanged since they formed in the early Universe. Rubin Observatory’s ten-year Legacy Survey of Space and Time will detect thousands of previously-unseen, faint brown dwarfs, vastly increasing the numbers of these ancient relics that scientists have been able to study thus far, and unlocking clues to the Milky Way’s formation and evolution. Image Credit: NSF-DOE Rubin Observatory/NSF NOIRLab/AURA/J. da Silva

 Jointly funded by the U.S. National Science Foundation and the U.S. Department of Energy’s Office of Science, NSF-DOE Vera C. Rubin Observatory will reveal a never-before-seen population of brown dwarfs beyond the sun’s local neighborhood. Brown dwarfs are excellent for helping scientists disentangle the history of the Milky Way galaxy’s formation and evolution, which was strongly influenced by mergers with smaller, nearby galaxies. By studying the properties of ancient brown dwarfs, scientists can trace them to their original galaxies that merged with the Milky Way and thereby reveal changes in how Milky Way stars formed over the billions of years since the beginning of the universe.

The NSF-DOE Vera C. Rubin Observatory on Cerro Pachón in Chile. The Rubin Observatory will observe the entire visible southern sky every few nights over the course of a decade, capturing about 1000 images of the sky every night and giving us a new view of our evolving universe.

The NSF-DOE Vera C. Rubin Observatory on Cerro Pachón in Chile. The Rubin Observatory will observe the entire visible southern sky every few nights over the course of a decade, capturing about 1000 images of the sky every night and giving us a new view of our evolving universe. Image Credit: NSF-DOE Rubin Observatory/AURA/B. Quint

From its vantage point on Cerro Pachón in Chile, Rubin Observatory will take wide, detailed images using the world’s largest digital camera, covering the entire visible sky every few nights. Rubin’s near-infrared capability, combined with its wide field of view and ability to see deeply into space, will capture the light from brown dwarfs more than three times further away from the sun compared to current astronomical surveys.  This increase in distance means an even bigger increase in the total volume of space available for scientists to find and study brown dwarfs, offering scientists a much larger sample of these faint objects.

“Rubin will reveal a population of ancient brown dwarfs about 20 times bigger than what we’ve seen up to now,” said Aaron Meisner, associate astronomer at NSF NOIRLab and Rubin Observatory’s community science team member. 

Source: NSF