The Andromeda Galaxy, also known as Messier 31 or "Great Andromeda Nebula", is one of the most distant celestial objects that man can see with the naked eye; you can take advantage of the constellations that surround it to locate it in the starry sky. You can vaguely perceive it at simple sight, but a telescope or binoculars allow you to see it with greater clarity. To optimize observation, go out on a moonless winter or autumn night; the first time it is quite complex to locate the galaxy, but once you find it you shouldn't lose it anymore.
Steps
Method 1 of 3: Finding the Galaxy
Step 1. Get away from the city lights
Light pollution at any level hinders the observation of the Andromeda Galaxy; it is better to get away from urban areas, from street lamps and from illuminated parking lots. Go hiking in the mountains, find an isolated camp or other dark area.
Step 2. Wait for your eyes to adjust to the dark
This galaxy is not as bright as the stars surrounding it; when you go out to observe the starry sky, allow yourself at least a quarter of an hour to get used to the absence of light; then you realize that you can see a greater number of stars.
Step 3. Use a celestial map to find out where the galaxy appears in the sky
The position of the stars, constellations and galaxies changes according to the season; look for a map drawn for the month you are making your observations.
- Usually, you can find these cards online for free; they are also sometimes sold at planetariums or astronomy clubs.
- The star maps also indicate what is the best time to see the Andromeda Galaxy based on the season.
- For example, in the months of September and October the galaxy rises to the east in the northern hemisphere and should be exactly over the observer's head at midnight.
- If you live in the Southern Hemisphere, you need to look for it towards the northern horizon in December; sometimes it may not even arise.
Step 4. Download an astronomical observing application
There are many software that help find Andromeda, the other galaxies, the stars and that modify their celestial chart according to your geographical position, hemisphere, season and time. Some of these are: Star Chart app, NightSky app and GoSkyWatch.
Step 5. Find the Cassiopeia constellation
You can spot the Big Dipper and look for the bright star adjacent to it. This is the Polar star or Polaris. Between the Polar Star and the Big Dipper you should see Cassiopeia, made up of five stars arranged in a "W" shape that point down directly towards the Andromeda Galaxy.
Step 6. Find the constellations of Andromeda and Pegasus
The second looks like a huge rectangle; you should see two lines of stars extending from the upper left corner representing the constellation of Andromeda.
Remember that the constellation and the Andromeda Galaxy are two different celestial elements
Step 7. Look for a halo, a smudge between Pegasus and Cassiopeia
The galaxy you are looking for is located right between the constellation of Pegasus and the tip of Cassiopeia and looks like a fuzzy or hazy oval.
Step 8. Draw a line between the stars Mirach and Mu Andromedae
Start with the star located in the upper left corner of Pegasus. The constellation of Andromeda starts from this point; follow it along two stars downwards, you should see two (one above the other): these are Mirach and Mu Andromedae. If you draw a line through them and extend it beyond Mu Andromedae, you should come across the Andromeda Galaxy.
Mu Andromedae is less bright than Mirach and is also closer to the galaxy
Step 9. Search for satellite galaxies
If you are using a telescope, you may see two faint blurry spots on the side of the galaxy. One of these corresponds to M32 and is smaller and closer than the core of the galaxy itself; the other point instead represents NGC 205 which is larger and more distant. In both cases they are Andromeda's satellite galaxies.
Method 2 of 3: Choose the Tools
Step 1. Start by finding the galaxy with the naked eye
You can see that of Andromeda without the help of special tools: it appears as a hazy and faint oval in the night sky. Once you recognize the area it is in, you can see it better with binoculars or a telescope.
Step 2. Use the binoculars to zoom in and zoom in on the image
This optical instrument allows you to see the galaxy up close. Once located with the naked eye, slowly raise the binoculars and adjust the focus until you can see the Andromeda Galaxy. It should look like an oval cloud.
You can use normal binoculars for this operation; you should opt for a 7x50, 8x40 or 10x50 model
Step 3. Use a telescope for more detailed observation
A classic 200 mm reflector model allows you to see the core of the galaxy and the two satellites; this celestial element is so large that you cannot see it entirely with the telescope.
If you have decided to use the telescope, set the minimum magnification; although to the naked eye the galaxy appears very small, thanks to the telescope its image is very large
Method 3 of 3: Optimize Observation
Step 1. Search the Andromeda Galaxy in the fall or winter
If you live in the Northern Hemisphere, the best season is from August to September; if you live in the south, you have to concentrate your efforts between October and December. In these periods the galaxy appears as soon as the sky gets dark.
It can be seen all year round in the Northern Hemisphere, although it is difficult to locate in other seasons
Step 2. Choose a new moon night
The presence of this celestial body reduces the brightness of the stars; if you go outdoors during the waxing or new moon phases, you can enjoy a clearer view of the Andromeda Galaxy.
- If the moon is full, you will have great difficulty locating the galaxy.
- The new moon occurs once a month; use an online moon phase calculator to find out which night is best for astronomical observations.
Step 3. Check the weather forecast to make sure the sky is not cloudy
Any cloud can prevent the vision of the stars; read the weather reports before you go out, to make sure the sky is clear.
Advice
- What you can actually see is the core of the galaxy, as the outer arms are very faint. You can try to photograph it to make it stand out, but chances are you need to select an extended exposure time, use a telescope photo adapter, and an image overlay program, such as Registax or ImagesPlus.
- Remember to dress appropriately for the climate, especially in the cold months.
