When galaxies clash, is star formation heightened or quenched? The
Taffy galaxies (UGC 12914/5) provide an excellent setting to probe this
question. These two galaxies, shown above in a representative-color
optical image from the Sloan Digital Sky Survey, collided head on just
25–30 million years ago, resulting in a bridge of turbulent gas that
stretches across the space between them. A team led by Philip Appleton
(California Institute of Technology/Infrared Processing and Analysis
Center) carried out new Atacama Large Millimeter/submillimeter Array
(ALMA) observations, the locations of which are marked with red circles
in the image above, to study this interacting pair of galaxies. The
team’s observations of carbon monoxide gas suggest that the filaments
and clumps within the bridge that connects the two galaxies are likely
gravitationally unbound. Without a source of pressure to keep them
together, these potentially star-forming features are likely to
dissipate within 2–5 million years. Despite this, star formation presses
on in isolated regions. To learn more about the results of this
galactic interaction, be sure to check out the full article below!
Citation
“The CO Emission in the Taffy Galaxies (UGC 12914/15) at 60 pc Resolution. I. The Battle for Star Formation in the Turbulent Taffy Bridge,” P. N. Appleton et al 2022 ApJ 931 121. doi:10.3847/1538-4357/ac63b2
By Kerry Hensley
