A new fossil galaxy discovered through a systematic visual search of legacy survey images with the Mayall 4-meter telescope led by Dr. David Martinez Delgado could teach scientists about the formation of galaxies and confirm their understanding of cosmology and dark matter.
According to Dr. Michelle Collins, an astronomer at the University of Surrey in the United Kingdom and the lead author of the paper announcing this discovery, “have discovered a new, extremely faint galaxy whose stars formed very early in the Universe’s history. This is the first time a galaxy this faint has been discovered around Andromeda using an astronomical survey that wasn’t designed for the purpose.”
The dwarf galaxy known as “Pegasus V” is located on the outskirts of Andromeda and appears as a few sparse stars hidden in the sky.
The discovery was made in collaboration with the National Science Foundation’s NOIRLab and the International Gemini Observatory.
According to Emily Charles, a Ph.D. student at the University of Surrey who was also involved in the study, “The issue with these extremely faint galaxies is that they have very few of the bright stars that we use to identify and measure their distances. The large 8.1-meter mirror on Gemini enabled us to find faint, old stars, allowing us to both measure the distance to Pegasus V and determine that its stellar population is extremely old.”
In the near future, more astronomical facilities will be looking into researching faint galaxies.
The discovery was published in the Royal Astronomical Society’s Monthly Notices.