Galaxy

The Whirlpool Galaxy, also known as M51, is a magnificent face-on spiral galaxy. It is interacting with a smaller companion, NGC 5195, a dwarf galaxy connected to its larger neighbor by a tidal bridge of dust. The bridge is visible in the image silhouetted against the central region of the smaller galaxy.

One of the brighter nearby galaxies, NGC 2903 was somehow missed by comet hunter Charles Messier when he compiled his famous list of objects not to be mistaken for comets. Nonetheless, this barred spiral is an attractive telescopic object.

The Andromeda Galaxy (M31) is the closest spiral galaxy to our own Milky Way. It is visible to the naked eye as a faint smudge on a dark moonless night; it is impressive in a small telescope; but it takes a long exposure photograph to reveal its full extent and structure.

These two spectacular galaxies are neighbors, located near the bowl of the big dipper. M82 is an irregular edge-on galaxy that shows red gas and dark clouds. Its neighbor M81 is face-on, and displays stately grand spiral arms.

The Triangulum Galaxy (also known as the Pinwheel Galaxy or M33) is the third largest galaxy in our Local Group of galaxies (after the Milky Way and Andromeda). It is about three million lightyears away from us. Hence we enjoy a better view of it than any other galaxy except Andromeda.

Here are three different faint spiral galaxies that look quite different since we view them from different angles.

Here are three attractive galaxies that I was able to observe in the past week or so. You will notice that even though they are all spiral galaxies, they exhibit strikingly different appearance.

This is an update to my May 16 post. The sky was clear and moonless last Friday night, so I was able to check back in on the M61 supernova. A month later, it has faded only a little bit. I’m happy to report that the “seeing” was better this night, so this image shows somewhat more detail in the galaxy compared to my earlier images.

Here is an interesting field of galaxies in the constellation Virgo. The brightest is Messier 49, an elliptical galaxy. It is perhaps five times larger than our Milky Way galaxy and about 60 million light years distant. Since elliptical galaxies have no discernable structure, they just appear as fuzzy blobs.

NGC 4565, the Needle Galaxy, is one of the most prominent and famous edge-on spiral galaxies in the sky.

If you’ve ever seen a picture of another galaxy, odds are that it was of this one, the Andromeda galaxy, also known as M31. At a distance of 2.54 million light years from us, it is closer and hence appears larger than any other galaxy (apart from the two Magellanic Clouds in the southern hemisphere that are small satellites of our Milky Way). And it is on a collision course with us and will collide with our Milky Way in about four billion years.

This supernova was discovered on May 6. It is expected to continue to brighten for several days before fading away over several weeks.

M94 is a face-on spiral galaxy whose spiral arms hug the middle and wind very tightly into the core. It is sometimes called the Cat’s Eye galaxy or the or Croc’s Eye Galaxy. It is about 16 million light years from the Earth. Around the brilliant circular disk is a ring of active star-forming regions, revealed in astrophotography as blue young star clusters. This artifact delineates it from the faded outer ring of an older yellowish stellar population.

The Sombrero Galaxy (also known as M104) is a lenticular galaxy about 31.1 million light-years) from Earth. The galaxy has a diameter of approximately 30% the size of the Milky Way. It has a bright nucleus, an unusually large central bulge, and a prominent dust lane in its inclined disk. The dark dust lane and the bulge give this galaxy the appearance of a sombrero hat. Its large bulge, its central supermassive black hole, and its dust lane all attract the attention of professional astronomers.

The Leo Triplet is an interesting group of three mutually interacting galaxies that are often observed and photographed within a single field of view. The Leo Triplet includes spiral galaxies M65 (lower right), M66 (lower left), and NGC 3628 (upper left). This group of galaxies is found in the constellation Leo, all of them are about 35 million light years from the earth.

Here is a face-on view of the barred spiral galaxy Messier 83, the southern pinwheel galaxy. (It is believed that our own Milky Way galaxy would look very much like M83 if we could view it from outside, although the Milky Way is about twice as large as M83 is.) Notice the bright central nucleus, the well-formed spiral arms, the central bar, and the dark dust lanes.

The Owl Nebula (also known Messier 97) is a planetary nebula located approximately 2,030 light years away in the constellation Ursa Major. When William Parsons observed the nebula in 1848, his hand-drawn illustration resembled an owl’s head. It has been known as the Owl Nebula ever since. The nebula is approximately 8,000 years old. It is approximately circular in cross-section with a little visible internal structure. The nebula is arranged in three concentric shells, with the outermost shell being about 20–30% larger than the inner shell. The owl-like appearance of the nebula is the result of an inner shell that is not circularly symmetric, but instead forms a barrel-like structure aligned at an angle of 45° to the line of sight.

Here are two nearby galaxies taken from my back yard with my new astrograph telescope. M81 is face-on and its neighbor M82 is edge-on. Dust clouds in the latter are especially noticeable.

M51, better known as the Whirlpool Galaxy, is a magnificent face-on spiral galaxy. The Whirlpool Galaxy is interacting with a smaller companion, NGC 5195, a dwarf galaxy connected to its larger neighbour by a tidal bridge of dust. The bridge is visible in images of the pair silhouetted against the central region of the smaller galaxy. It lies at an approximate distance of 35 million light years from Earth.