The interior of the crater has a higher albedo than the surroundings, so the crater appears bright when the Sun is overhead.

albedo of

Wikipedia contributors. (2024, January 26). Langrenus (crater). In Wikipedia, The Free Encyclopedia. Retrieved March 4, 2024, from https://en.wikipedia.org/w/index.php?title=Langrenus_(crater)&oldid=1199122063

How to find and observe Almach (TOTS#6) (eyesonthesky.com) Gamma Andromedae is a rather interesting double star within our own Milky Way galaxy. First, the primary is a very yellow star, and the secondary an intense blue. At over 350 light years distance, the light from these stars reaching us today left not long after Christian Huygens proposed that Saturn had rings… in the 1600’s! But the star gets even stranger. The dimmer blue secondary is itself a double star, averaging a Sun/Neptune distance. Stranger still, the primary of THAT system is ALSO double! So Gamma Andromedae is really a quadruple star system.

Langrenus (crater) (Wikipedia) Langrenus is an impact crater located near the eastern lunar limb. The feature is circular in shape, but appears oblong due to foreshortening. It lies on the eastern shore of the Mare Fecunditatis. To the south is the overlapping crater pair Vendelinus and the smaller Lamé.