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Stargazing Can I see anything other than the planets with a 4 telescope?

  1. Sep 23, 2009 #1
    Can I see anything other than the planets with a 4" telescope?

    I saw Jupiter (and four of its moons), Neptune, Mars and Venus but they were all really tiny so I was wondering if the planets are so tiny does that mean I wouldn't be able to see any of the other objects, like galaxies and nebulae, at all?

    With the eye-pieces I have the maximum magnification is 100x.
     
    Last edited: Sep 23, 2009
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  3. Sep 23, 2009 #2

    chemisttree

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    Re: Can I see anything other than the planets with a 4" telescope?

    You will be able to see most of the Messier objects at reasonably dark sites (mag 5 skies or better). In larger cities, you are probably limited to planets and larger brighter nebulas like the great nebula in Orion and perhaps M57 when it is directly overhead (like it is now just after dark). You will defintely see star clusters like M13 and galaxies like Andromeda when they are overhead... not so much as they drop toward the horizon in light polluted skies. Your local light pollution will limit what you can see visually, of course.

    The focal length of your scope will determine how bright an object you can see as well. A shorter focal length scope will give brighter objects but they will be smaller. The Celestron 102mm refractor is an f 9.8 scope and gives fairly bright views and good magnification. When the sky is right I can see most of the Messier catalog using it from my home just outside the city lights of San Antonio.
     
  4. Sep 23, 2009 #3

    turbo

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    Re: Can I see anything other than the planets with a 4" telescope?

    To see faint stuff like galaxies, you need dark skies and good contrast. Often lower-power eyepieces with wider fields can help you sweep up faint galaxies. If you have a very dark place to view from and will allow yourself plenty of time to get dark-adapted, those will both help a lot, as will using averted vision. If you look directly at a faint low-contrast object, it can be tougher to pick it out of the field than if you look just a bit away from the object.
     
  5. Sep 23, 2009 #4

    Nabeshin

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    Re: Can I see anything other than the planets with a 4" telescope?

    Don't forget about the moon!
     
  6. Sep 23, 2009 #5

    russ_watters

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    Re: Can I see anything other than the planets with a 4" telescope?

    Didn't you get a barlow lens? A 4" telescope is capable of good resolution to a magnification of about 250x and that provides good views of the planets out through Saturn.

    For galaxies and nebulae, you don't need more magnification, you need less. Most such objects are relatively large in the sky, they are just dim. M31, for example, is a spiral galaxy that is 8x the apparent diameter of the moon or roughly 700x the apparent diameter of Jupiter.

    So then the answer to your initial question is yes, there are several dozen nebulae and galaxies (not to mention star clusters) that are accessible with your telescope.
     
  7. Sep 23, 2009 #6
    Re: Can I see anything other than the planets with a 4" telescope?

    The one I have is 102 mm and Focal Length 800 mm, so I guess things will be fainter :(

    How dark? The faintest stars I see with the naked eye are around 3.5 magnitude. I'm not sure, but I think that's very bad :/ I drive about an hour out of the city but I still have to go to somewhere inhabited.

    :D It's the prettiest!

    Yes, I got a 2x barlow lens. When I got it they told me that it gives a wider field of view, but the Wikipedia article doesn't mention the field of view at all.

    But a larger aperture would still be better because it'd gather more light, right?

    Thanks :D
     
  8. Sep 23, 2009 #7

    George Jones

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    Re: Can I see anything other than the planets with a 4" telescope?

    The Double Cluster in Perseus should look quite beautiful with low magnification (lower than 100) and a 4" scope. At lowest power, you might be able to fit the coathanger asterism (in Vulpecula, near Summer Triangle) in your field of view. You might also have a look for the Dumbell Nebula (M57, again near Summer Triangle). At 100x, the Ring Nebula (mentioned by chemisttree as M57) might look like a small, dim ring. I can make out the ring shape at 81x with an 8" scope.
     
  9. Sep 23, 2009 #8

    Nabeshin

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    Re: Can I see anything other than the planets with a 4" telescope?

    Wow. Are you sure? 3.5 is TERRIBLE, like, standing in the center of the city bad. I live only 15 miles out of Chicago and I can see 4.2 on a clear night. And I thought THAT was disgusting.
     
  10. Sep 24, 2009 #9
    Re: Can I see anything other than the planets with a 4" telescope?

    I don't know :( I drive nearly 45 minutes from the city, and I stop at a kind of a tourist village where only the street lights are on at night.

    I'm still going to try anyway!

    Edit: Oh I forgot to ask, will any of these things mentioned here be visible or detectable in the guide (the tiny telescope attached to the bigger one)? And if I'm going to upgrade so as to be able to see these things better, what should I get? The one I have is a refractor btw.
     
  11. Sep 24, 2009 #10

    turbo

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    Re: Can I see anything other than the planets with a 4" telescope?

    If you want to find faint stuff to look at, you should invest in a decent set of charts and learn how to star-hop (use brighter stars to find the approximate location to point your scope, scan with long eyepieces for lower-power and wider fields, and then switch to other oculars when you have bagged your prey). Unless your finder is very large (aperture) with superior optics (not what you usually find on commercially-available scopes) you're not going to see many deep-sky objects in it. A zero-power finder like a Telrad can be a big help if you're starting out. The sky looks just like it does to your naked eye, and the views correspond to what you see in your charts. Don't be afraid to use your eyes, even without a finder. My refractor's OTA is long enough that I can often point it to a nearby bright star, estimate the amount of offset in RA and Dec and sweep up faint objects without using a finder.
     
  12. Sep 24, 2009 #11

    russ_watters

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    Re: Can I see anything other than the planets with a 4" telescope?

    No, it gives a narrower field of view - more magnification.
     
  13. Sep 25, 2009 #12
    Re: Can I see anything other than the planets with a 4" telescope?

    This is what I do, but I'm still having a lot of trouble finding things that are not visible to the naked eye. For example today I was trying to find M57 which was very close to Vega. I got Vega but I couldn't find M57 :( The only thing that I couldn't see with the naked eye but eventually managed to find was Neptune (because it happened to be directly above Jupiter), and it wasn't a very rewarding sighting. And if the star that I'm aiming for is not too bright I have no idea how to tell if I'm pointing at the wrong star.

    What's that?!
     
  14. Sep 25, 2009 #13

    turbo

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    Re: Can I see anything other than the planets with a 4" telescope?

    You need a little practice, but charts and a zero-power finder can get you to a lot of faint stuff. I mentioned Telrad because they have been in the business a long time, but Orion sells some nice zero-power finders, too. Essentially these finders project a dot or other kind of reticle on a reflective surface so that it appears to float in your naked-eye view of the heavens. Once you get used to the skies in your viewing area you can estimate what's visible in your constellations by leaning what magnitude stars you can see.

    Don't be too disappointed if you don't pick up M57 right away - it's a low-contrast object that is extremely difficult from light-polluted locations. May I suggest that you try epsilon Lyra? At low power, it's an obvious double star, but with higher magnifications and good optics, you will see that each component of the double is actually another double-star. Among amateurs, it's often just called the double-double.
     
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