The young age and close proximity to earth allows astronomers to study star-formation down to the lowest masses. Astronomers have found a number of so called
free-floating planetary-mass objects that probably formed like stars and are called
planetary-mass brown dwarfs. Multiple works did detect planetary-mass objects (PMOs) in IC 348. These PMOs were found to have masses as low as 4-5 from searches with
Hubble and Spitzer. Additionally it was found that around 46% of these objects are surrounded by a
disk. The relatively young age of the IC 348 star cluster has facilitated the discovery of three low-mass brown dwarfs. As these objects cool over time, they become more detectable, particularly in their youth. Recent observations conducted in 2023 by the
James Webb Space Telescope (JWST) have confirmed these findings, identifying them as the smallest free-floating brown dwarfs on record, with the lightest among them weighing a mere three to four times the mass of Jupiter. This groundbreaking revelation, announced by NASA's James Webb Space Telescope team, challenges existing paradigms in the field of stellar formation. Found within the IC 348 cluster, located 1,000 light-years away in the Perseus star-forming region, these brown dwarfs serve as intriguing celestial entities, bridging the gap between stars and planets. Some share striking similarities with gas giants, boasting masses just slightly larger than Jupiter. JWST has discovered new PMOs down to 2 . Spectroscopy with
NIRSpec has shown that the brightest PMOs resemble
L dwarfs. The faintest and lowest mass objects do however show absorption of
hydrocarbons at 3.4 μm, which lead the researchers to propose a new spectral type of "H". Two objects in this sample showed
infrared excess due to a disk around the PMOs. == Gallery ==