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Use constellation Cassiopeia to find Andromeda galaxy


Tonight for November 9, 2015

Tonight … find the Andromeda galaxy, the next-nearest spiral galaxy to our Milky Way.

David Smith of Michigan wrote:

What is the easiest way to find the Andromeda galaxy at this time of year? I tried a couple times with my telescope but had no luck.

The image at right shows the view of the Andromeda galaxy through a telescope. But we hope you’re not looking through the eyepiece of your telescope when sweeping through the sky for this galaxy. That would be hard. You need a wider field of view to spot the galaxy.

For starters, try scanning for the Andromeda galaxy with the unaided eye or binoculars. In a dark sky, you might spot it, as the early stargazers did before the days of star charts and optical aid. The Andromeda galaxy is a large hazy patch in the night sky.

But what if you can’t find the Andromeda galaxy just by looking in a dark sky? Many stargazers star-hop via the W-shaped constellation, Cassiopeia – shown on the chart on the top of the page. Cassiopeia appears in the northeast sky at nightfall and swings high to the north as evening progresses. It’s shaped like an M or W. Note that one half of the W is more deeply notched than the other half. This deeper V is your “arrow” in the sky, pointing to the Andromeda galaxy.

Remember, on a dark night, this galaxy looks like a faint smudge of light.

Once you’ve found it, try again with binoculars or your telescope. The Andromeda galaxy is about 2.5 million light-years away, just a hop and a skip in astronomical terms. Like our Milky Way, this large spiral galaxy is teeming with hundreds of billions of stars.

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Andromeda Galaxy from Chris Levitan Photography.

Bottom line: What’s the easiest way to find the Andromeda galaxy? Many use the constellation Cassiopeia, which is shaped like an M or W.

More about M31: Great galaxy in Andromeda

Use Great Square of Pegasus to find Andromeda galaxy

Easily locate stars and constellations during any day and time with EarthSky’s Planisphere.