How to Find Andromeda Galaxy in the Night Sky

For any new astronomer or anyone who has just acquired a telescope,  one of the most challenging things to do is finding objects in the night sky, especially when these things are beyond our solar system.

You may have seen all the wondrous images in books, magazines, on the internet, or documentaries, and you will start to wonder how much you can truly see with your own eyes through a telescopic lens. 

But where do you even begin when you are looking for something in deep space through a telescope, and how powerful does your telescope need to be to see something as distant as the Andromeda Galaxy? 

There are many ways to find this wondrous sight, you can use the most used amateur method, star-hopping, you can refer to constellations, or use a stargazing app, or online sources. But, which is best? 

Why is it so hard to find? Perhaps a result of light pollution or is it just that you need to be in the right place at the right time?  Or, maybe it is only visible in certain places? We will answer all of these questions. 

Here, we will talk you through how to best find the Andromeda Galaxy in the night sky.

What is the Andromeda Galaxy?

The Andromeda Galaxy is a member of a group of galaxies of which our own Milky Way galaxy is a part of. The Andromeda Galaxy is also known as M31.

Although this galaxy is 2.5 million light-years away from where you are standing right now, it is so insanely bright that you can see it unaided, from a dark enough sky, with no light pollution or cloud cover.

This is due to its light magnitude of 3.3. If you live in a heavily light-polluted area, you will find that it is too difficult to see with the naked eye. In cities, this means that you will have to use a telescope and even then you are unlikely to see any more than its bright core. 

Andromeda has four dwarf galaxies nearby, M32, M110 are two of the main ones that you can view. They are visible in the night sky like bright stars, the smallest of the two sits above Andromeda, this one is M32, and the larger one is below Andromeda and is M110.

These are the nearest and brightest elliptical galaxies. Then the other two are more distant and are in Cassiopeia (we will talk about this more later), these two are NGC 147 and NGV 185. They sit above the Andromeda Galaxy.

Although there are several dozen minor galaxies that lay closer to our Milky Way than this galaxy, the Andromeda Galaxy is the closest large spiral galaxy to ours. It is the brightest galaxy that you can see from our planet.

To the naked eye, this galaxy may appear as a smudge of light that is larger than a full moon. This is only possible in ideal viewing conditions; dark sky, no light pollution, or cloud cover. 

Where is the Andromeda Galaxy?

Unsurprisingly and unironically the Andromeda Galaxy is located within the constellation of Andromeda. This is best viewed in fall in the Northern Hemisphere where it is usually viewable during all dark conditions; from dusk until dawn, in perfect conditions.

In the middle of fall, late September until early October, the Andromeda galaxy will rise in the eastern sky and will stay overhead around midnight and will fade in the west as dawn breaks. Much like our moon does as our Earth turns. 

During the winter months, Andromeda is viewable overhead and you can use planispheres or certain astronomy software for assistance in spotting it in the night sky overhead. If you are looking up and you cannot see the galaxy, but you know you are looking at the right time, you can star-hop to find it.

One of the easiest recommended ways to do so is to the constellation of Cassiopeia, this constellation is easy to use for this, as it is easy to find, shaped like the letter ‘M’, it is northward on the sky’s dome.

Or if you know where the Big Dipper is, then you can use that the Big Dipper and Cassiopeia move around Polaris (the North Star) much like the hands of a clock, always opposite each other. 

Finding Andromeda with a Telescope

The first step to seeing the Andromeda Galaxy for the first time is to know what to expect when you see it. It is likely that it will not look like you will see in an online image or a print photo.

It is also nowhere near as bright as its neighboring stars. If you are looking at the sky and are looking in the correct place it may look like a hazy patch of light that is about as wide as the moon, it may lead to thinking that it is nothing more than a smudge on your eyepiece, but this is exactly what you are looking for. 

There are different ways to find Andromeda with different telescopes and techniques. 

Using Cassiopeia to Find Andromeda

Cassiopeia is one of the easiest constellations to find in the sky after the Big Dipper, and it is also very close to the Big Dipper, which makes it a perfect point of reference for seeking out Andromeda.

It is also what is called a circumpolar constellation, meaning that it is always out at night, so is a permanently reliable point of reference. 

You can search for this constellation either by referring to its angle to the Big Dipper or by using the ‘V’ shape of the stars; Shedar, Caph, and Navi to point towards M31 (Andromeda.) 

Using Stars to Find Andromeda

If you know the stars a little better you can use a viewfinder to star hop and find your way to Andromeda. Hop down the two stars from Alpheratz to Mirach.

Once you can see this star, move northwest and you will find Mu Andromedae. The Andromeda Galaxy lies at the same distance, around 1.3 degrees just past Mu Andromedae. 

This is easily sought out in reference to the Big Dipper and Cassiopeia. 

Mu Andromedae is close enough to the Andromeda Galaxy that if you are gentle with your viewfinder and eyepiece then you may be able to get both of these in your view at the same time, provided you use a low range of magnification. This could be a very fascinating sight and is worth trying to see. 

Looking Through a Telescope

To view Andromeda through a telescope,  you will need patience and concentration. You may notice that the oval is thickest and brightest at its center. You should see an oval blur that seems to be rather thin and long if you use a 4” scope or more. 

You may also notice tonal changes in the brightness as you look from the center to the edges. It is also more circular than oval in its center, this should also be noticeable to you.

If your scope is smaller you may not see all this detail, but you can see dust lanes against the light. We recommend a 4” or more scope to get the best view of this galaxy. 

Through a Large Telescope

Another option for you, if you haven't bought your telescope yet, is a Dobsonian telescope. This is an altazimuth-mounted Newtonian telescope that vastly increases the size that is available to amateur astronomers.

If you own one of these, you will be star-stuck by what this provides you as a sight. Giving your eyes time to adapt to the faint light, while the night is darkest, you will be able to discover the wider reached and more finite details of this vista.

If you use an 8” or more telescope you may be able to see the captivating arms of stars that surround the core and make it referred to as a ‘Spiral Galaxy’. 

Andromeda Overall

The Andromeda Galaxy is a fascinating vision to see through your telescope. It is bright and viewable through any telescope, but with the best, you can see its amazing details.

It is often seen as a sister galaxy to us, being the nearest spiral galaxy to us and being used by many astronomers and scientists to understand the origin and evolution of this type of galaxy. 

This galaxy is also interestingly approaching ours (the Milky Way) at around 100-140 kilometers per second. It also has a very crowded double nucleus and has a massive star cluster deep in its center.

It also curiously has at least one supermassive black hole within its core. Its spiral arms are distorted by the gravitational interactions of its two companion galaxies; M32 and M110. 

So take to your telescope, look up at the black night, and find yourself lost within the stars, gazing at a galaxy a couple of million lightyears away. You’ll be captivated. 

Andy Morgan