NGC 3079

NGC 3079 is a barred spiral galaxy about 50 million light-years away, and located in the constellation Ursa Major. A prominent feature of this galaxy is the "bubble" forming in the very center (see picture below). The supermassive black hole at the core has a mass of $2,400,000 solar mass$.

Two supernovae have been observed in NGC 3079: SN 2001ci (type Ic, mag. 18.3), and SN 2013ee (type II, mag. 15.5).

Center Bubble
The bubble forming in the center of NGC 3079 is believed to be about 3000 light-years wide and to rise more than 3500 light-years above the disc of the galaxy. It is speculated that the bubble is being formed by particles streaming at high speeds, which were in turn caused by a large burst of star formation. This current bubble is thought to have been created about one million years ago, and computer modeling suggests that there is an ongoing cycle of forming bubbles, with a new bubble forming approximately every 10 million years.