Deep-Sky Objects in October 2021
The new astronomical season began recently all across the globe, which means you can go on a hunt for some new celestial objects! In today’s article, we’ll focus on deep-sky objects and tell you about notable galaxies and star clusters you can see this October. The dates on our list were chosen to match the time when the objects are highest in the sky and thus are most easily observed.
To quickly locate any of the deep-sky objects listed below, you can use our astronomy apps: Sky Tonight or Star Walk 2.
What are deep-sky objects?
The term “deep-sky objects” denotes faint astronomical objects outside our Solar System: namely galaxies, nebulae, and star clusters. This term is mainly used by amateur astronomers. There are several catalogs of deep-sky objects, the most popular being the Messier catalog and the NGC catalog.
October 1: M110
M110 (also known as NGC 205) belongs to the class of dwarf elliptical galaxies. It is the brightest and largest of the satellite galaxies orbiting the Andromeda Galaxy. On October 1, M110 will have a magnitude of 8.1 and will be visible in the constellation Andromeda through medium-sized telescopes. This galaxy is mostly a Northern Hemisphere target that is unobservable from locations south of 28° south latitude.
October 2: Andromeda Galaxy and M32
The Andromeda Galaxy (also known as M31 or NGC 224) is the closest large spiral galaxy to the Milky Way. Initially, this galaxy was considered to be a nebula, so you can sometimes hear it being called the Andromeda Nebula, too.
The Andromeda Galaxy is a very popular object among beginning astronomers. And no wonder, as it’s the most distant object you can see with the unaided eye! On October 2, this galaxy will shine with a magnitude of 3.4 in the constellation Andromeda. We advise you to use binoculars or a small telescope for its observation.
Another object you can see on October 2 is M32 (NGC 221). It’s the second brightest satellite of the Andromeda Galaxy (after M110). You can find it in the sky near its parent galaxy. At a magnitude of 8.1, M32 will be observable through a medium-sized telescope.
Note that both the Andromeda Galaxy and M32 cannot be seen from latitudes much south of 28° south latitude.
October 3: Sculptor Galaxy
The NGC 253 spiral galaxy goes by several names, including the Sculptor Galaxy, Silver Coin, and Silver Dollar Galaxy. It’s one of the brightest galaxies in the sky and can be seen through binoculars (though using a telescope is still preferable). On October 3, NGC 253 will have a magnitude of 7.1 and will be located in the constellation Sculptor. This galaxy is easily visible from the Southern Hemisphere, but can’t be seen from locations much north of 44° north latitude.
October 4: Small Magellanic Cloud
The Small Magellanic Cloud (SMC, NGC 292) is a dwarf irregular galaxy positioned close to our Milky Way. On October 4, the Small Magellanic Cloud will shine with a magnitude of 2.7 in the constellation Tucana. You can try to spot this bright galaxy with the naked eye, but it’s still better to use binoculars or a small telescope. The SMC is visible from any location south of the equator but is practically unobservable from the Northern Hemisphere.
October 7: NGC 362
The next deep-sky object on our list lies close to the Small Magellanic Cloud in the sky; it is only observable from the Southern Hemisphere as well. NGC 362 (also known as Caldwell 104) is a spectacular globular cluster that contains hundreds of thousands of stars. On October 7, NGC 362 will have a magnitude of 6.6 and will be positioned in the constellation Tucana. Grab a pair of binoculars or a small telescope to see it in the sky.
October 15: Triangulum Galaxy
The Triangulum Galaxy (also known as M33 or NGC 598) is the third-largest galaxy in the so-called Local Group which includes the Milky Way and Andromeda galaxies. On October 15, its visual magnitude will reach 5.7, so it will be bright enough to be observed with binoculars. Look for this spiral galaxy in the constellation Triangulum. The Triangulum Galaxy is a northern sky object that is difficult to observe from the Southern Hemisphere.
October 26: Double Cluster
The Double Cluster (Caldwell 14) occupies an area twice the size of a Full Moon in the sky and consists of two open clusters. NGC 869 (also known as h Persei) represents the Double Cluster’s western half, while NGC 884 (χ Persei) represents its eastern half. On October 26, NGC 869 will be shining with a magnitude of 4.3, while NGC 884 will have a magnitude of 6.1. You can use binoculars or a small telescope to observe both halves of the Double Cluster in the constellation Perseus. Note that these deep-sky objects are unobservable from locations south of about 30º south latitude.
October 31: Fornax Dwarf Galaxy
The final deep-sky object on our list is quite a challenging astronomical target. The Fornax Dwarf Spheroidal Galaxy is a satellite of the Milky Way. It is positioned in the constellation Fornax and contains six globular clusters that are easier to see than the galaxy itself. On October 31, the galaxy will have a magnitude of 9.0 and will require at least a medium-sized telescope to be discerned. If you have a small telescope, you can take a chance with the galaxy’s bright globular clusters. The Fornax Dwarf Galaxy is a southern sky object that is difficult to observe from locations north of 35° north latitude.
Observe deep-sky objects in Sky Tonight!
In the stargazing app Sky Tonight, you’ll find more than 90,000 deep-sky objects. The app includes galaxies, nebulae, and star clusters from different catalogs: Messier, NGC, Caldwell, Collinder, Melotte, IC, PGC, and others. All deep-sky objects are available for free from the start. To find an object you’re interested in, just tap the magnifier icon, write the object’s name or catalog designation in the search field and tap the target icon. Sky Tonight will immediately show you the object’s location in the sky above you.
Thanks for reading this article. If you manage to see any of the deep-sky objects mentioned above, please share your experience with us on social media. To learn more about deep-sky objects, take our fun quiz named “Guess the Nebula!”. We wish you clear skies and successful observations!