The Andromeda Galaxy, also known as M31 or the "Great Spiral Galaxy", is one of the most distant objects visible to humans with the naked eye. The galaxy spans between 2, 2 and 3 million light years. Finding it the first time can be a little tricky. However, once you find it, you will have no more trouble finding it.
Note: The best time to find the location of the Andromeda galaxy is between August and the end of March. That way, if you're having trouble finding it, bookmark this page and try again later. Also know that these galaxies are easier to find in the northern hemisphere than in the southern hemisphere.
Step
Step 1. Use binoculars for your first attempt to locate the Andromeda galaxy
Even if you don't need anything other than the naked eye, using binoculars will make it a lot easier for you as a beginner. Binoculars also give you a wider field of view than telescopes, which is important for a beginner. Also, choose a cloudless night, and if you live in an area where there are no stars, you may want to go elsewhere.
Step 2. Find all three constellations to get a benchmark
You need to find Pegasus, Cassiopeia and Andromeda. Pegasus is a winged horse in Greek mythology, and the last star in Andromeda forms the Square of Pegasus; It is easy to find as it is one of the largest geometric shapes in the night sky. Cassiopeia has an easy-to-see W or M shape and the last two stars can be used as clues to the constellation Andromeda. Andromeda is a princess saved by Perseus from a monster in Greek mythology. The table seen here shows the night sky at 35°N and set on December 1 at 20:00 p.m. local time, but can be used later in the afternoon before that date and slightly after.
Step 3. Look for different characteristics
Pegasus is the easier constellation of the three, as it looks like a large square shape; this is called the Great Quadrilateral in Pegasus. Cassiopeia is even easier to find because it looks like a big "M" or "W". Andromeda lies between the two.
Step 4. Draw a line from the star Sirrah (also known as Alpheratz) from the periphery of Pegasus and Andromeda to the star Ruchbah in Cassiopeia
Step 5. Draw a line from the star Mirach through the star Mu Andromedae and continue along the first line
Bear in mind that Mu Andromedae is fainter than Mirach.
Step 6. Look at the area just to the southeast where the two lines meet, along the second line, using binoculars (or a small telescope - see next step)
You will find a faint oval of light. This is the Andromeda galaxy.
Step 7. Use a telescope to see it in more detail
An ordinary 20 cm long reflector telescope can help you see 1000 times farther than the Andromeda Galaxy, so you will be able to see it very well using a standard telescope. When using a telescope, especially when the sky is a bit foggy, try also to find Casseopeia, then use Cassiopeia's "M" shape to point to the star Mirach. After locating Mirach in the telescope, continue to Cassiopeia to find a fainter star, then further away from that direction until you find two fainter stars and a faint triangular object with these two stars. This is the galaxy.
- If you look closely with binoculars or a telescope, you can find two faint faint spots next to it. One of them, M32, is smaller and closer to the actual galactic core. The other, NGC 205, is more difficult to identify, larger in size, and further away from the actual galaxy. Both are companion galaxies of Andromeda.
- You'll probably be able to find it if you use a GOTO or computer telescope. If you use equatorial coordinates and know how to adjust the telescope circle, the galaxy is at RA 00h43m, DEC +41deg16'.
- If you know how to use a telescope, you'll know that its narrow field of view compared to binoculars can help you find it more accurately and therefore more difficult. So, if you are new to telescope use, skip this step until you feel more confident.
Tips
- The Andromeda Galaxy can be seen even in relatively clear skies, but it may be a bit more difficult to find the fainter stars. Therefore, you need to observe a slightly wider area.
- If you can observe a dark place away from a street lamp, you are more likely to find this object.
- While tools like binoculars and telescopes aren't needed to find these galaxies, they can make your view much clearer.
- What you see is actually the core of the galaxy, with a very faint exterior. You might want to try taking a photo to make it pop, but it might take a long exposure time, a camera adapter, and photo composing software like Registrax or ImagesPlus.
- In the opposite direction of the three/four bright stars, you may find two bright stars, and another dim star that looks like a double star, forming a triangle. If you draw a line from the dim star in the direction between the two brighter stars, and continue along, you may find the Triangulum Galaxy, and yet another elusive yet bright galaxy.
- The Andromeda Galaxy is 200,000 light years away and has 400 billion stars. This galaxy is called M31 because it is the 31st object on Messier's list of scattered celestial bodies.
- Two other galaxies that can be easily seen from Earth with the naked eye are: the Large Magellanic Cloud and the Small Magellanic Cloud. M33 can be seen from dark places and some keen eyed observers have spotted M81.
- Constellations are a collection of stars like a puzzle point. If you connect the dots-namely stars-and have a great imagination, the image will look like an object, animal or human. For example, Orion is a constellation of stars that the Greeks thought resembled a great giant with a sword strapped to his belt.
Warning
- This may be difficult to do in the Southern Hemisphere.
- Remember to dress according to the weather, especially in the colder months.