Ultra-diffuse galaxies are generally quenched dwarf galaxies with no gas reservoirs, they are therefore unable to form new stars; as a result, the star population in such galaxies is very old, similar to what we see in globular clusters.
Dr. Barth walks us through the discovery of UDGs by Allan Sandage and Bruno Binggeli in 1984.
The activities and materials provided free for the How Do You Know? program are based upon Dr. Barth’s award-winning book: Astronomy For Educators. This book is used as a resource in more than 5,700 schools across the United States and in more than 50 countries world wide. The book is published as an Open Educational Resource Text by the University of Arkansas Library Press.
- Return to the How Do You KNOW? index of programs.
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