What can merging star clusters teach scientists about the formation and evolution of dwarf galaxies, which are smaller galaxies than our Milky Way and orbit larger galaxies? This is what a recent study published in Nature hopes to address as an international team of researchers investigated the origins of nuclear star clusters (NSCs), which are some of the densest regions in the cosmos. This study has the potential to help researchers better understand the formation and evolution of stars and the clusters they form throughout the universe.
For the study, the researchers used high resolution images from NASA’s Hubble Space Telescope to observe 80 dwarf galaxies and discovered five dwarf galaxies that possess unique NSCs at the center of their galaxies. The goal of the study was to ascertain how these clusters form and evolve over timescales that are much smaller than our Milky Way has experienced. In the end, the researchers found that these clusters form from the migration and merging of star clusters in relatively short timescales, or approximately 100 million years. Additionally, the researchers noticed odd streams of light coming from these clusters and concluded that globular clusters cannibalize each other at the center of these dwarf galaxies.
“We were surprised by the streams of light that were visible near the center of the galaxies, as nothing similar has been observed in the past”, said Mélina Poulain from the Space Physics and Astronomy Research Unit at the University of Oulu and lead author of the study.
While NSCs have been observed to exist in most galaxies, specifically spiral galaxies like our Milky Way, this study underscores the importance of studying galaxies of all shapes and sizes to better understand the formation and evolution of stars throughout the universe.
What new discoveries about NSCs will researchers make in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
Sources: Nature, EurekAlert!
Featured Image: Stars clustered at the center of our Milky Way Galaxy. (Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA); Acknowledgment: T. Do and A. Ghez (UCLA), and V. Bajaj (STScI))
