Object 170: Don't Forget the Feedback

NGC 2639 may look like an ordinary spiral galaxy, but it contains an active galactic nucleus with jets of gas that have emerged from that nucleus in four different directions, which is, to use the technical term, quite weird.

LGS 3 (also known as the Pisces Dwarf Galaxy) is a nearby but faint dwarf galaxy that has provided some interesting clues as to how stars formed in the early universe.

While not many professional astronomers have spent much time looking at the open cluster Messier 103, it is still a spectacular object to see in an amateur astronomy telescope.

Astronomers have been studying the radiowave emission from the cluster of galaxies Abell 4038 quite intently and have provided both conventional and unconventional explanations for its origin.

The southern open cluster IC 2602, also known as the Theta Carinae Cluster or the Southern Pleiades, may not be as famous as some open clusters visible from the Northern Hemisphere, but it is still a good place for professional astronomers to study young stars, and it's also a good amateur astronomy target.

Baade's Window is an unusual hole through the interstellar dust in the Milky Way's disk through which astronomers can very clearly see the stars near the center of our galaxy.

Markarian 231 is now widely recognized not only as the closest quasar to Earth but also as a very bright ultraluminous infrared galaxy.

The pulsar PSR J1022+1001 is one of a small subclass of pulsars named millisecond pulsars because they rotate one every few milliseconds.

The lenticular galaxy NGC 1172 contains two different populations of globular clusters, which indicates something about the history of the galaxy.

Dy Pegasi is an SX Phoenicis type variable star, and SX Phoenicis type variable stars are a subset of Delta Scuti type variable stars, and this episode explains why that is confusing but what it also actually means.