The Webb Space Telescope has discovered the smallest brown dwarf known to date, with a mass of only 3 4 times that of Jupiter, which continues to challenge the theory of star birth.
A fundamental question that every astronomy textbook asks is: How small can stars be? We know that brown dwarfs are the dividing line between the smallest and largest stars, and that they originally formed like stars, dense enough to collapse under their own gravity, but never large enough to ignite fused hydrogen, hence the jokes that brown dwarfs are failed stars.
Recently, the Webb Space Telescope found a record-breaking smallest brown dwarf, which floats freely in interstellar space and is only 3 4 times more massive than Jupiter.
Penn State astronomer Kevin Luhman and ESS astronomer Catarina Alves de Oliveira studied the star cluster IC 348 in the constellation Perseus, an area about 1,000 light-years away. Using the Webb Telescope's near-infrared camera (NIRCAM) to image the center of the star cluster, the team identified three interesting brown dwarfs based on their brightness, with a surface temperature of 830 1,500 and a mass of 3 8 times that of Jupiter, and the smallest of them weighing only 3 4 times the weight of Jupiter.
Three new brown dwarfs were discovered, one of which is only 3 4 times more massive than Jupiter.
Although these objects also fall within the mass range of gas giants, researchers believe that they are unlikely to be giant planets ejected from the planetary system, first of all, most of the stars in the IC 348 cluster have low masses and are unlikely to form giant planets; Second, the cluster is only 5 million years old and may not have had enough time for the giant planets to form and pop out of the system.
But existing theories still can't explain how the brown dwarf, which is 300 times smaller than the Sun, was born, and these new discoveries have prompted scientists to continue to think about the strange intersection between stars and planets.
New** published in The Astronomical Journal.
***nasa）