James Webb Space Telescope spies massive shockwave and baby dwarf galaxy in Stephan's Quintet

By Robert Lea
published about 11 hours ago



A team of astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) and the James Webb Space Telescope (JWST) discovered a recycling plant for warm and cold molecular hydrogen gas in Stephan’s Quintet, and it’s causing mysterious things to happen (Image credit: ALMA (ESO/NAOJ/NRAO), M. Weiss (NRAO/AUI/NSF))

Shockwaves created by a collision between the galaxies of Stephan's Quintet and an intruder galaxy are driving strange processes in the intergalactic medium, the tenuous clouds of warm-to-hot hydrogen plasma that exist in the space between galaxies.

New observations made with the James Webb Space Telescope (Webb or JWST) and the Atacama Large Millimeter/submillimeter Array (ALMA) provided astronomers with a good view of intruder galaxy NGC 7318b as it violently forces its way into this group of galaxies at a relative speed of around 1.8 million mph (approximately 800 kilometers per second). That's fast enough to travel from Earth to the moon and back again in just over 15 minutes.

This violent invasion of Stephan's Quintet is triggering a shockwave several times as large as the Milky Way that is rippling through the interstellar plasma and kickstarting a "recycling plant" for warm and cold molecular hydrogen gas between the five galaxies. In addition, astronomers found a giant cloud of gas breaking apart to form a less-dense "fog" of warm gas; the JWST/ALMA observations also show a tail of warm gas forming from what might be a collision between two clouds, and even the formation of a new galaxy.

The discovery of these phenomena could help scientists better understand how turbulence influences the intergalactic medium and how collisions affect the formation of stars and the evolution of galaxies in general.

More:
https://www.space.com/james-webb-space-telescope-stephans-quintet-shockwave-baby-galaxy