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Stargazing woes

  1. Oct 25, 2014 #1
    I've had a telescope for a few years. I know pretty basic stuff - and I can easily find planets when they are in the sky (mostly because I know Venus is around sunrise/sunset, and Jupiter & Saturn are non-twinkling bright objects in the sky). I know a few constellations - Cassiopeia, Orion, Ursa Major, etc. Bright ones of course. In the last few days I have attempted to find M31 in the sky to no avail. I live in the suburbs of Saint Louis and I have been able to see objects, that I know the location of, of similar magnitude to M31. I use Stellarium and I know M31 is up and around but I cannot for the life of me navigate the sky. Unfortunately the excess light pollution has made it difficult for me to recognize other constellations.

    I feel like I may have passed up M31 when scanning the sky because it would only look like a smeared star in the telescope...

    I use Celestron NexStar 6SE. It has an AutoAlign feature in it but ever since I bought it I have never been able to get it to work. Although at this point I wish I had picked up a huge Dobsonian because I never use the electronic features and I would have rather paid the extra $$ for more aperture/resolution than a useless autoalign feature. Maybe I'm using it wrong; Though I have attempted it many times over the last few years. Also doesn't help I'm surrounded by trees!

    The moon and the planets look wonderful in it. I've peered at the Orion Nebula when I had taken a trip to an area with less light pollution.I've been sort of bored lately because the planets don't come out in the Fall, at least not until very early morning and I don't really want to get up for that.

    For anyone else living in central USA and in large cities - what have you been looking at lately?

    Also - out of curiosity, with my 6 inch telescope would I be able to differentiate Uranus from any other star?
     
  2. jcsd
  3. Oct 25, 2014 #2

    DaveC426913

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    M31 is quite large. It's extended disc is larger than the full Moon. It should be easily visible to the naked eye, though my night vision has never been good enough to see it, even though I've memorized the exact location.

    With a scope, you'll be able to distinguish its brighter central core, which should be a pretty extended blob filling your viewfinder.
    I always find Jupiter and his moons to be by far the most fascinating. I like to set up my scope and check every night over a couple of weeks * and plot the moons' positions on a graph (x-axis is Jovian diameters, y-axis is days) to watch them dance around Jupiter then plot their helical paths.

    * I tool live in a mega city, but Jupiter and his children are easily bright enough to resolve from my backyard, meaning taking the scope out nightly is no inconvenience.

    Also, I like sketching Mars. I'll sketch what I see then go to an online virtual telescope, which will show me what Mars actually looks like at the date/time and see how accurate my sketch is.

    Drat. It's been too long now. I can;t find either of my sketches, nor can I find the real time Mars simulator site.
     
    Last edited: Oct 25, 2014
  4. Oct 26, 2014 #3
    I actually found Andromeda tonight! I certainly did not mistake it for a star when I came across. I managed to identify Pegasus and it being next to Andromeda I was able to find M31. I could resolve a faint elliptical cloud and bright core. I could also barely, ever so barely see that one tiny galaxy that is by Andromeda on the top left (forgot its name). Now I can at least point at the sky where the galaxy is.

    Yeah, Jupiter is always a favorite of mine to look at. Unfortunately it's not out in the evening this time of year. I'm excited for winter because I find the winter sky very fascinating.

    What kind of telescope do you use? Mars is interesting, but no more than a pinkish disc through my lens.
     
  5. Oct 26, 2014 #4

    DaveC426913

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    I've got a 6" Newtonian on an equatorial mount. Not sure of the actual brand name. Bought it second-hand.
     
  6. Oct 27, 2014 #5

    Andy Resnick

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    I live near a large city, light pollution definitely restricts what I can view. Even so, with my 5.5" f/2.8 refractor and Google Sky, I'm able to star-hop to pretty much anything worth looking at.
     
  7. Oct 27, 2014 #6

    DaveC426913

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    Yep. Starhopping is a critical skill.

    Well, unless you have a GOTO computer on your mount. But that's kind of cheating.
     
  8. Oct 27, 2014 #7

    DaveC426913

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    Same here, but astronomy is about patience and observation.

    Looking at that tiny disc over time such as 30 minutes or so, you will be able to distinguish a lot of subtle surface features. Sketching really hones this skill.

    A helpful point is to ensure your vision is fully night-adapted. That's hard to do in a big city. I go to a park where I can get away from streetlights. Takes about a half hour. Usually I have to find the one perfect spot in the whole park where a tree obscures individual lights. Then I keep them from getting in my eyes.
     
  9. Oct 27, 2014 #8
    I do, but unfortunately in the years I've owned it I have never been able to get it to work. I've been sort of "star-hopping" without knowing it in the last few days since I picked the scope back up. Helped me find those faint nebulae!

    I live in the suburbs of the city so there's not many lights around that will ruin my sight. I have a large back yard, but there's a lot of trees so my view is restricted from the east.

    Yes, astronomy is about patience and observation. Would staring at M31 for a while reveal any more details? When I looked at it, it was a faint smudge but I've seen others under similar viewing conditions who were able to see more. Ring Nebula is probably just too darn faint.

    I really want to see a globular cluster though. Haven't been able to find one!

    I have the book "Turn Left at Orion" but it's kind of hard to use until you know where the stars are...star-hopping will come in handy I suppose !
     
  10. Oct 28, 2014 #9

    DaveC426913

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    Definitely. Especially as your night vision improves.

    Night vision takes about a half hour to fully kick in. And if you accidentally get a glimpse of a street light, it's gone again.

    Other tricks:
    - use your peripheral vision. It is more sensitive to low light levels than your focal vision. If you look just off to the side of where M31 is, you'll actually see it better.
    - don't "stare". Let your eyes keep moving a little. If you try to stare at a single spot, your retina will get "fatigued" and stop picking up details.
     
  11. Oct 28, 2014 #10
    thanks for the tips. Did not realize how "delicate" night vision is. I need to get everything outside before sundown so i don't come in looking for a book or laptop or something.

    Yes, this is something odd I have noticed. Any reason to why this is? Not necessarily restricticted to astronomy, but when I use peripherals in darkness i see everything better! I use it a lot when looking at faint(er) stars in the sky too.
     
  12. Oct 28, 2014 #11

    DaveC426913

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    Yup. And if you DO need light, use a very low power flashlight, cover it with a red gel, and never point it near your eyes. Just like they (used to) use in a photo darkroom.



    Unequal distribution of rods versus cones in your retina.

    Rods are sensitive to low light levels, but sacrifice acuity and colour.
    rcdist.gif
     
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