ultra-diffuse

Definitions

1. Extremely diffuse.
2. Specifically, designating a type of galaxy with a very low proportion of visible stars compared to the Milky Way, and hence a very low luminosity.

Examples

“In the next sections we study⟳ the properties of galaxies that satisfy⟳ our criteria to be ultra diffuse, and consider⟳ the contribution from galaxies in the fore- and background using the CFHTLS fields.”

“The galaxy, called NGC1052-DF2, is about 65 million light⟳ years away. It is almost as big as the Milky Way but is “ultra-diffuse,” meaning it contains just a vanishing fraction of the stars found in our galaxy—only 1 percent, in this case.”

CEFR level