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I will be going to the desert this month and it's my understanding that the night sky will be very dark there. I've got some practice locating the planets but I'd really like to get a look at a nebula or galaxy. I understand from Is the Celestron astromaster 130 EQ Model able to see nebulas and galaxies? that nebulas and galaxies are visible with modest magnification. I'd really appreciate some tips on locating stuff that's cool to look at other than planets and the moon. I've got an AstroMaster 114 (114mm, f/8.77) with a couple of eyepieces and a Barlow lens.

I've searched a bit and these targets seem like a good short list.

  • Albireo
  • Orion Nebula, M42
  • Andromeda Galaxy, M31
  • Hercules Cluster, M13

I understand that my telescope has an equatorial mount and I do take care to orient it northwards and adjust it to match my latitude, but I've never truly bothered to center it on the north star. I find locating the north star a bit daunting. All the instructions I've encountered say to locate the big dipper (aka the plow) and follow the line of two if its stars. Finding constellations is not my strong suit -- especially with the haze and obstructions here in Los Angeles. I can usually find Orion pretty well, though.

I have an app on my iphone called Planets which I find quite helpful for locating the planets, but I'm not sure if it will operate properly out there where there's no telephone service. It also doesn't provide any tools to identify or locate deep space objects. It's just for planets.

My telescope does have some "setting circles" (little dials demarcated in degrees or hours, see photo) but my understanding of ascension and declination is sketchy at best and I also understand that these are not especially accurate. I'm wondering if they might have some use to get me in the ball park of the objects I'm seeking -- maybe help me at least find the constellation from which I can locate the deep space objects of interest.

So to summarize, I'm hoping for tips on locating the north star and establishing a proper baseline position for my telescope and I'm also hoping for good, basic instructions for locating some interesting, non-planetary objects to view in my scope.

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Those targets are good choices for beginners at the right times of year. However, in June M42 is a daytime object, and M31 rises in the wee hours, leaving only M13 and Albireo in the evening. Other good summer targets include:

  • M8, the Lagoon Nebula
  • M11, the Wild Duck Cluster
  • M57, the Ring Nebula

Precise polar alignment is only required if you plan to take long exposure photographs. Setting circles help when you can't see much of the sky at once, e.g. under an observatory dome or partial cloud cover. In order to be useful, the right ascension circle must be reset each observing session, or more frequently if your mount isn't motorized.

The Skymaps.com Evening Sky Map can help you find your way around the night sky. It shows the whole sky as it appears 2-3 hours after sunset, including several deep-sky objects visible with a 100mm or larger telescope. A multi-page atlas such as the S&T Pocket Sky Atlas provides enough detail to actually get those objects in the telescope's field of view. A little red light for the maps minimizes the impact on your night vision.

With practice, you can learn to locate any target of interest by triangulation, first among the bright stars, then among the faint stars in between. For example, M13 is about 60% of the way from Arcturus to Vega and 30% of the way from η Her to ζ Her. A detailed atlas also shows two 7th magnitude stars each ¼ degree away from M13 in an obtuse triangle. If the object does not at first appear in the telescope field, carefully sweep the surrounding area. Some mounts provide fine motion controls to help with this.

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  • $\begingroup$ This answer is really helpful! You rightly point out that a lot of these objects are behind the sun now so we can't see them. Ring Nebula looks awesome. Thanks also for clarifying the setting circles issue. I'm certainly not motorized. That Skymap is really good. I've printed it out, and I'll email the PDF to my phone. Triangulation sounds like just the ticket, but it sounds like one would need a lot more detail about surrounding stars. Any thoughts on how to obtain that info? $\endgroup$ – S. Imp Jun 7 at 15:12
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    $\begingroup$ @S.Imp Revised to answer that question. $\endgroup$ – Mike G Jun 9 at 3:48
  • $\begingroup$ Sad to report I was unable to find any Messier objects in the desert this weekend. I took Skymaps printout and was able to find relevant constellations in some cases with help of an iPad app, but distance between nearby stars on that map was just way too great to reasonably search with my scope. E.g., trying to find M87 we tried to search area between Vindemiatrix & Denebola. It was just too much sky. It' also frustrating to turn on a light or phone to see the sky map and then try to remember how it looks while waiting for your eyes readjust until you can actually see stars again. $\endgroup$ – S. Imp Jun 11 at 0:30
  • $\begingroup$ @S.Imp That's what the little red light and multi-page atlas are for. Thanks for the update and better luck next time. Some objects are easier to locate than others. $\endgroup$ – Mike G Jun 11 at 0:35
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If you have a Laptop or Notebook you can download one of several planetarium programs like Stellarium or Cartes du Ciel. They will display large areas of the sky that will help orient you initially. Zoom the computer view to match the view in your finder then zoom in again and get a view on the laptop that is close to the view in your eyepiece. Compare the star field views between the laptop and telescope then move the telescope accordingly. Many years ago there was a method of finding objects called star hopping. This is basically the same procedure but with a bit of assistance.

Patience, practice and persistence. Get hold of as much as you can before heading out to the desert. Nothing else will help you as much as those.

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  • $\begingroup$ I do have Stellarium installed on my work station and really like it. I don't think I'll be able to get it on a laptop in time for this trip, unfortunately. $\endgroup$ – S. Imp Jun 7 at 15:13

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