Which giant molecular cloud lies about 120 parsecs from the Milky Way's center?

The giant molecular cloud lying about 120 parsecs from the Milky Way’s center is Sagittarius B2.

Also called Sgr B2, this enormous cloud of gas and dust sits near the Galactic Center, about 390 light-years from it. It spans roughly 45 parsecs, contains around three million solar masses of material, and is among the Galaxy’s most active stellar nurseries. Its main regions are commonly labeled Sgr B2(N), (M), and (S).

Sgr B2 is famous not only for star formation but also for its rich chemistry. Radio and millimeter-wave observations have detected many complex molecules there, including methanol, ethanol, and ethyl formate. The latter is associated with a raspberry-like aroma in terrestrial chemistry, inspiring the playful description “raspberry rum.”

A common mix-up is confusing Sgr B2 with Sagittarius A*, the supermassive black hole at the Galaxy’s center. Sgr B2 is a molecular cloud, not the central black hole; its location is offset from Sagittarius A* by about 120 parsecs.