M31, the Andromeda Galaxy, with its companion galaxies, M32 (below) and M110 (aka NGC 205, above), ... [+]
Have you ever seen a giant galaxy with your own naked eyes? That’s exactly what’s on offer to stargazers this season—but only for those that know exactly where to look.
The galaxy in question is the famous Andromeda Galaxy, also known as M31, which is the most distant object you can see with your naked eyes. If you’ve got a pair of binoculars you’ll get a beautiful close-up—but this isn’t a great sight in most telescopes.
Here’s everything you need to know to see the Andromeda Galaxy with your own eyes.
What is the Andromeda Galaxy?
It’s the closest large galaxy to our own Milky Way. A spiral galaxy—just like the Milky Way—it’s around 2.5 million light-years from us, so each time you look at it you’re seeing how it look 2.5 million years ago. That’s how long it’s taken for its light to travel here.
It contains around a trillion stars and is a member of the Local Group of galaxies, which includes our own Milky Way and about 30 others. It’s essentially our sister giant galaxy.
The Andromeda Galaxy is really special to stargazers. Since it’s the only giant spiral galaxy we can look at closely, it’s essentially how we know what the Milky Way looks like from the outside. From where we are on one of its spiral arms, it’s hard to tell.
It’s also a top-tier celestial sight that doesn’t look that special in all but the largest of telescopes. So this is one for the naked eye and binoculars—this one belongs to stargazers.
Why is it called the Andromeda Galaxy?
It gets its name from the constellation it’s found within the boundaries of—Andromeda. In Greek mythology, Andromeda is the daughter of the king Cepheus and his wife Cassiopeia. Both of those constellations are close to the constellation of Andromeda, which is rising high in the eastern night sky after dark this month.
Here’s a sky-chart to find the gout location of the Andromeda Galaxy.
How to find the Andromeda Galaxy
The darker your night sky, the better. That’s always the case for stargazing, but for the Andromeda Galaxy, it goes double. This month the Andromeda Galaxy is virtually above you in the darkest patch of sky possible, but being away from light pollution will help enormously with getting naked eyes-on with this iconic object. However, any pair of binoculars will help you pick-out M31 rather easily from underneath any kind of urban sky.
So here’s how you do it—by finding the halfway point between two bright stars and my shy-charts both above and below.
- Looking east after dark, find the W-shaped constellation of Cassiopeia and the “Great Square” of Pegasus. Mars is right below it for the moment.
- Identify the brightest star in Cassiopeia, Schedar, which is at the point of a V in the W-shape.
- Now find Alpheratz at the corner of the “Great Square” of Pegasus.
OK, now we have two ways of actually finding the Andromeda Galaxy—one hit-and-hope, and the other more precise:
Andromeda Galaxy: hit-and-hope
Draw an imaginary line to link-up Schedar and Alpheratz. The Andromeda Galaxy is just below the halfway point on that line. Point your binoculars in this general area and scan around for a “faint fuzzy.”
Andromeda Galaxy: more precise
Either with your naked eyes or through binoculars, find Alpheratz and then come down in a curve to another bright-ish star, then another—that’s Mirach in the constellation of Andromeda. Now turn 90º and go upwards past one bright-is star, then another. The Andromeda Galaxy is just above it.
Here’s a skychart showing how to find the Andromeda Galaxy once you’re in the right region of the ... [+]
How to observe the Andromeda Galaxy
The Andromeda Galaxy is known as a “faint fuzzy,” but there are ways of looking at it that make it look truly stunning. Whatever instrument you use to look at it—naked eyes or binoculars—when you find it, it will be a distinctly oval object. Now look slightly away from it. That might sound crazy, but your peripheral vision is more sensitive to brightness—and when we’re talking about the collective brightness of a trillion stars, it’s worth doing things properly!
If your view through binoculars is wobbly, lean back against a wall to steady your body and bring your elbows into your chest to make still your arms.
If you have trouble finding it, identify where you think it is—using my sky-charts—and come down to the horizon. Remember what that point on the horizon is—perhaps it’s marked by a tree, a house or a building. Now try going back up to the Andromeda Galaxy along a line going upwards from that point on the horizon. It’s better to scan up and down that line that it is to scan in all directions. Be patient and you’ll find it.
As you galaxy-gaze, ponder that fact that the Andromeda Galaxy is on a collision course with the Milky Way; we’ll eventually merge in about four billion years to become a giant elliptical galaxy.
Wishing you clear skies and wide eyes.
