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CAC's Spaced Out Challenge: The Croc's Eye in the Sky and a Sombrero

This week, we go bigger than a cluster of a few million stars. We're hunting galaxies.

For urban observers, this usually means a lot of looking and frustration and throwing one's binoculars on the pavement, and the wife screaming at you for breaking her birding binoculars. Not so with this week's challenge object for you city dwellers: M94, the "Croc's Eye Galaxy". For those of you blessed with living in the country, far away from light pollution, I have a challenge for you too: M104, the "Sombrero Galaxy". Pics, maps and tips below.

As always, some tips:
1- Do your hunting when the moon isn't out. To figure this out, you can consult a host of sites, but my favorite is the U.S. Navy's here.
2- Find a dark site. For residents of cities and the burbs this has some difficulty, but for the urban sky challenges find a nearby lot, perhaps the end of a street, with good views of your horizon and few obvious lights. You needn't go on an hour-long trip to spot a lot of the objects highlighted.
3- An eye patch covered over one eye for one hour will do wonders in finding faint objects. However, be sure not to ruin that by using a regular flashlight to read a chart or your phone. Always use a red LED lamp to avoid ruining your night vision (for most people, that takes an hour to regain).
4- If you wish to look for more objects, or want to customize your own star maps, there are a host of free planetarium programs online. My favorite, used to generate all the maps below, is Stellarium, which you can download here.
5- Invest in a set of decent astronomy binoculars, and if you can, a modest telescope. Far from breaking the bank, the average dob-mounted 8" reflector runs about $350 new these days, a fraction of the cost of a similar telescope just a few decades ago.
6- Check the weather, and I don't mean the weather channel. Dark sky forecasts include seeing and transparency calculations that can mean the difference between frustrating haze and crystal clear views. Check out Danko's Clear Dark Sky Charts for the most accurate astro-weather you'll ever find.

Onto this week's objects.

For you city and suburb dwellers, try your luck at the Croc's Eye Galaxy:

Messier 94 is a barred spiral galaxy with a unique dual-ring structure whose inner ring is an intense region of star formation. The galaxy is also unique for apparently having little dark matter, though that could just be an observational glitch. M94 is one of the brightest galaxies and thus one of the easiest targets for amateurs, even those living in areas rife with light pollution.

Here's a view of the target sky from a heavily-light-polluted sky. You'll notice the familiar asterism of the Big Dipper, which makes up part of the larger constellation Ursa Major:

Draw a line from Arcturus to the bottom star in the back of the dipper. The only bright "star" that will appear along it is your starting point, Car Caroli. Once you've found the target "jump off" star, just follow the hops and let your mind make the patterns:

And the final view from city skies through the binos:

For the telescope owners, here's how to star-hop in the eyepiece to M94:

And a medium-power final result:

For those of you blessed with more rural skies, here's your challenge:

The Sombrero Galaxy.

The Sombrero is easily one of the most striking galaxies known, and for you older morons, it should be memorable: it's one of the interstellar objects featured in the credits of the original Outer Limits. This galaxy is easily visible with binoculars as small as 8x42s, but to save yourself the hassle I recommend a modest pair of 15x70s. As for the telescope owners, aim for this if you're armed with at least 4" of aperture, and if you hope for details, an 8" reflector or better. Got that? Good. Now let's find it.
*STOP* What about those of you stuck looking from Los Angeles, or Chicago, or Atlanta? Why should the hillbillies get all the fun? For a guide to local dark sky sites, look no further than the Dark Sky Finder. Hundreds of entries across North America, often with parking/ state park/ amenities information and driving directions.
Ok, back to the hunt.

This time, look more to your south, though depending on the time of the evening and month, your "jump off" stars, Spica and the odd trapezoid that makes up Corvus, may be in the East or West:

You'll use your eyes to make the first few star hops, and then use your binoculars or telescope:

With your telescope, feel free to crank up the power on that last hop, and if you "lose" your place, just downshift to your low-power eyepiece and re-hop.

As always, why not hit up Ace's Amazon storefront for your astro needs? The Celestron 15x70s mentioned above are a steal right now at $60, and with Comet ISON just around the corner, most manufacturers will continue offering deals on their scopes, eyepieces, mounts and other accessories.