A new fossil galaxy, discovered through a systematic visual search for ancient survey images using the Mayall 4-meter telescope, led by Dr. David Martinez Delgado, could teach scientists how galaxies form and confirm their understanding of cosmology and dark matter.
dr. Michelle Collins, an astronomer at the University of Surrey, UK and lead author of the paper announcing the discovery, says they have found “a new, extremely faint galaxy whose stars formed very early in the history of the Universe. discovery marks the first time a galaxy so faint has been found around Andromeda using an astronomical survey not specifically designed for the task.”
Named “Pegasus V”, the dwarf galaxy is located on the outskirts of Andromeda and appears as just a few thin stars hidden in the sky.
The discovery was made in collaboration with NSF NOIRLab and the International Gemini Observatory.
Emily Charles, a Ph.D. student at the University of Surrey who was also involved in the study says that “the problems with these extremely weak” galaxies is that they have very few bright stars which we typically use to identify them and measure their distances. Gemini’s large 8.1-meter mirror allowed us to find faint old stars, allowing us to both measure the distance to Pegasus V and determine that the stellar population is extremely old.”
More astronomical facilities are investigating fuzzy galaxies in the near future.
The discovery was reported in Monthly Notices from the Royal Astronomical Society†
Michelle Collins et al, Pegasus V – a newly discovered ultra faint dwarf galaxy on the outskirts of Andromeda, Monthly Notices from the Royal Astronomical Society (2022). DOI: 10.48550/arXiv.2204.09068
University of Surrey
Quote: New discovery of fossil galaxies could answer important questions about universe history (2022, June 30), retrieved June 30, 2022 from https://phys.org/news/2022-06-fossil-galaxy-discovery- important-history. html
This document is copyrighted. Other than fair dealing for personal study or research, nothing may be reproduced without written permission. The content is provided for informational purposes only.