Astronomers Discover Distant 'Jellyfish Galaxy' Undergoing Gas Stripping
Researchers have identified COSMOS2020-635829, a galaxy experiencing gas stripping due to its movement through a dense cluster environment 8.5 billion years ago.
Astronomers have identified COSMOS2020-635829, a galaxy undergoing gas stripping as it moves through a dense cluster environment 8.5 billion years ago. This discovery, made using the James Webb Space Telescope (JWST), provides insight into early galaxy evolution.
COSMOS2020-635829, located at a redshift of 1.156, exhibits a symmetric stellar disk with a unilateral tail of star-forming knots. These features suggest the galaxy is experiencing ram pressure stripping, a process where intergalactic medium pressure removes gas from a galaxy, potentially halting star formation. The tail's star-forming regions are characterized by young stellar populations, with stellar masses around 100 million solar masses and star formation rates between 0.1 and 1 solar mass per year.
Dr. Ian Roberts, a Banting Postdoctoral Fellow at the University of Waterloo, stated,
"We were looking through a large amount of data from this well-studied region in the sky with the hopes of spotting jellyfish galaxies that haven’t been studied before. Early on in our search of the JWST data, we spotted a distant, undocumented jellyfish galaxy that sparked immediate interest."
This finding indicates that galaxy clusters were already harsh environments capable of stripping galaxies much earlier in cosmic history than previously thought. The research has been published in The Astrophysical Journal.