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  Cat's Eye Galaxy (M94) - Nov / MARCH

In this section you are going to learn where to look for the Cat's Eye Galaxy.

When to See The Cat's Eye Galaxy

The Cat's Eye Galaxy is best seen in the following months at the following times:

  • November, between 5am and 7am
  • December, between 3am and 5am
  • January, between 1am and 3am
  • February, between 11pm and 1am
  • March, between 9pm and 11pm

M94 - The Cat's Eye Galaxy

As we reach a quarter of the way through the year, we come to this chance to find our first galaxy.


NASA Picture of The Cat's Eye Galaxy


In this picture from M94's Wikipedia entry, you can see that it is a magnificent, classic example of what we expect a galaxy to be.

Sadly, it doesn't look this stunning in our own scopes, but I always find looking at galaxies to be mesmerizing. Just the thought that the faint, glowing cloud you see in your eyepiece is the home to an estimated 40 billion stars blows my mind.

This galaxy is about 16 million light years away from us and 30,000 light years from one side to the other. Its inner core, which is all we can hope to see from our backyards, is about 1 arcminute across, which is a little wider than Jupiter appears at its closest approach.

However, the Cat's Eye Galaxy is a lot fainter than Jupiter, making it harder to find. But, since this is true of many DSOs, don't let it put you off. Instead, get excited for the sense of achievement you will have when you get it centered in your eyepiece after the struggle of finding it!

Where to Find M94

We find this galaxy in the little constellation of Canes Venatici - don't worry if you've never heard of it before, I'll give you instructions on how to find it shortly.

For now, take a look at the screenshot below which shows where to see it at 10pm on a mid-March evening: around 40° above the horizon midway between northeast and east. Each shot is the same, both showing stars up to magnitude 4 (visible under light-polluted skies), but the left one has constellation lines in it whilst the right one does not.


Where to Find M94, With and Without Imaginary Constellation Lines


Now, let's take a quick close-up look at its location within Canes Venatici and then we'll figure out how to star-hop our way towards M94.


A Closer View of the Constellation Canes Venatici

Images Courtesy of SkySafari Pro - www.SkySafariAstronomy.com.


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How to Find M94 With Your Telescope

Now you know approximately where to find it, it's time for the precise stepping stones to seeing it in your eyepiece.

The two bright stars of Canes Venatici, Cor Caroli and Chara are easy to locate 'under' the handle of the Big Dipper, away from the north celestial pole (show as 'NCP' in the picture above).

Cor Caroli is the brightest at 2.9 whilst Chara shines at 4.2, which is still a bright star and visible in all but the most polluted skies.

The image below shows where to position these stars in your viewfinder (7° blue circle, left) or Telrad circles (red circles, right) to have M94 within easy reach of your eyepiece.


Where to Find the Cat's Eye Galaxy in Relation to Cor Caroli

Image Courtesy of SkySafari Pro - www.SkySafariAstronomy.com.


You can see in each picture that M94 is at right angles to the halfway point of the imaginary line that connects the stars Cor Caroli and Chara.

Start your hunt for M94 with a low magnification eyepiece (one with a higher focal length, e.g. 25mm or 30mm). Begin with the halfway point of that imaginary line centered in your finderscope. Move out from that line in the direction of the Big Dipper's 'handle', about one third of the distance between the two stars, and you will be very close to having M94 centered.

At this point you need to look through your telescope's eyepiece where, ideally, you'll be enjoying a 1° field of view, or larger. Gently move your telescope in that region until you see what looks like an out-of-focus star, there will be no detail of color or shade.

When you have it, firstly feel free to congratulate yourself: you have discovered M94.

Secondly, swap in a higher power of eyepiece (smaller focal length) to grow the size of the galaxy. Make sure to center the galaxy in your eyepiece first, so that you don't lose it as you swap eyepieces.

Use averted vision and more magnification to see if you can tease out any shapes to the light. If you have access to a suitable filter, this will also help your define some structure in the galaxy's shape.

One Last Challenge

After all that rewarding work, you may feel done. But, it would be a shame to pass up seeing the companion star of Cor Caroli, the brightest star we used earlier to find the Cat's Eye Galaxy.

Through your eyepiece, Cor Caroli will appear as two stars close together. The fainter companion star actually shines at at magnitude 5.5, so would be visible to the naked eye if it were further away from the main star.

From our perspective, the companion star is just 19" (arcseconds) away from its brighter main star, but, in reality, it is 5.6 light years distant from it!

Next Challenge

With the double star split and this galaxy seen, we move next to another galaxy: M51, the Whirlpool Galaxy.