Less than 100 million years old, the young stars are blue in the above false-color Galex image and seen to be well separated from the older yellowish stars of the galactic core.
Visible above M81 is a satellite galaxy dubbed Holmberg IX.
Studying the unexpectedly bright ultraviolet glow of this small irregular galaxy may help astronomers understand how the many satellites of our own Milky Way Galaxy developed.
M81, visible through a small telescope, spans about 70,000 light years and lies about 12 million light years away toward the constellation of the Great Bear (Ursa Major).
