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May 08, 2013
CAC's Spaced-Out Challenge: the Leo Triplet and Seashell Galaxy
This week, we jump back out into the extragalactic universe with two challenges, one for dark sky observers, and one for city-dwellers.
This also marks the last night in the annual Globe at Night survey. If the weather permits, take a few minutes to check out (or try to) Leo, and submit your observation. You may be surprised, after a few minutes of darkness adaptation, how many stars you can actually spot. Sky maps and images below.
With the moon close to new, we can enjoy the hunt for galaxies for a few more weeks before the Summer Milky Way takes center stage.
For Urban Astronomers:
The Leo Triplet (or at least two thirds)

About the object:
This small galaxy group is about 35 million light years distant and features two spiral galaxies, one face-on (M65), one more angled (M66), along with an unbarred spiral seen near-edge-on with a prominent dust lane (NGC 3628 ).
Messier 65 and 66 (FULP 115,116) jumped into my eyepiece a month back, to my total shock. With few guide stars in my bright skies, I had to do a triple-take to make sure I wasn't just hallucinating the two smudgy but obvious clumps of gas and stars before me. I even think I spotted the fainter member of this group, NGC 3628, but I'll need to recheck. So here's your challenge: do me one better. Find them all. Here's how.



For dark sky observers:
The Seashell (Southern Pinwheel) Galaxy, M83
M83, image credit ESO
About the object:
One of the closest and brightest barred spiral galaxies to us, M83 anchors a "group" that includes Centaurus A discussed on an earlier astronomy thread, though the grouping is now in question as the proper motion of these galaxies isn't what it first seemed. It's brightness places it well within binocular range in dark sky sites. Here's how to find it.



Now, if you have clear enough skies in the city to spot the brightest members of the Leo Triplet, you can take M83 on as well. Refer to stellarium or a similar program to reconfigure the above initial sky map to reflect your light-polluted view, and go from there. Much of the detail in the arms will be totally washed out barring you have an enormous instrument, but it's still worth a try and has been spotted by amateurs from less-than-ideal settings.
***
Expanded FULP List
First mentioned
here a few weeks back, I received a few emails from morons who made additional suggestions to the list. In addition to their suggestions, I scanned the interwebs and old issues of S&T for other surprise urban targets. Needless to say, the list grew a lot longer, with dozens of double stars, galaxies, and clusters added in.
As the year unfolds, I'll update certain entries on it to include finder charts and tips from individual astronomy threads. For now, enjoy the single most comprehensive list of objects that
can be spotted from severely light polluted skies, given filters, decent eyepieces, a modest telescope (for many of these, just binoculars), and patience
here. You may be surprised just how deep you can go from Queens: Quasar 3C 253, 2.5 billion light years distant, is well within your reach.
For those really bent on nailing all the items on the list, here are a few items you may find useful along the way, courtesy Ace's amazon store:
Celestron's O-III filter (for planetary and some emission nebula)
HERE
Orion's Ultrablock filter (for other nebula and some detail in galaxies)
HERE
Company Seven's excellent observer's chair
HERE
Orion's excellent economy barlow lens, the Shorty,
HERE
Orion's budget wide-field eyepiece, the Q70 (32mm)
HERE
and for those of you with the big bucks, a host of Televue eyepieces and barlows
HERE
For those looking for a first-time scope, particularly city dwellers, you can't go wrong with the 8" Orion XT8 dobsonian, which I've been using for over 2 years now. It has the highest rating for any scope on Amazon and if you buy it during the right months, it ships for free. 8" HERE
Until next time, clear skies and keep looking up!