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Terrible newbie question - what should I see

  1. Nov 19, 2003 #1
    Hi everyone,

    I have been reading these posts and it seems that I may need a bigger scope.

    I have access to a meade DS2070 It is a 70mm AP and a 700mm focal length and has a 25mm and a 9mm eyepiece, no barlow.

    My question is what should I be seeing? I have looked at mars and all I see is a bit clearer dot in the sky when using the 9mm. No way to see any moons. I have tried to look at saturn but it has not been good enough conditions to see it. But I dought that I will see the rings.

    Am I doing something wrong or is a 2.8" refractor just not good enough to see anything?

    thanks in advance for helping out a reall newbie...

  2. jcsd
  3. Nov 19, 2003 #2


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    A 2.8 inch refractor of decent quality is excellent for planetary observation. In fact, some of the most avid planetary observers swear by 3-5" apochromatic refractors.

    You'll probably never be able to pick out the moons of Mars in any amateur telescope. Doing so requires very careful techniques -- you have to observe at just the right time, and it's usually necessary to put Mars just out of the field.

    What you should see on Mars are some colorations due to the different soil types. You'll also be able to see some pock-marks, volcanoes on the surface.

    In many cases, the eyepiece is the weakest part of a commercial telescope system.

    My suggestion is to find some public star parties in your area. Take your telescope to them, and test some new eyepieces with your scope.

    - Warren
  4. Nov 19, 2003 #3
    That is a good idea Warren, unfortunalty I have not found any as of yet. As for volcanoes and such. Not even close!!!lol As I said, mars is just a little bigger dot using my 9mm. I was actually amazed at how little it was. I thought that I must be looking at a differnet object but I believe a verified that it was Mars. How dissappointing!


  5. Nov 19, 2003 #4


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    I was able to pick up Jupiters moons with a 4x Rifle scope, narrowly missed the shot!
  6. Nov 19, 2003 #5
    Hi jamminji,

    It sounds like you want to see some planetary details. Get yourself a decent quality 2x Barlow.

    The 2x Barlow will double your 9mm magnification from 78x to 156x and give you slightly less then the maximum that your scope can resolve (about 170).

    With the 2x barlow you should be able to see great detail on the moon, at least the major seperation of the rings of Saturn (probably not the Casseini Division, but maybe on a real good seeing day). Bands of color on Jupiter, possibly the Red Spot. Color variations on Mars surface including the polar ice caps and some hints of surface features. Clouds on Venus and lunarlike phases on Venus and Mercury

    Without the barlow, you should be able to see the Great Orion Nebula, the the four Galileon moons of Jupiter, split double stars, the Andromida Galaxy as a faint grey patch, most of the Messier Objects such as globular clusters such as M13, Pleiades (sp?) cluster.

    There are a lot of things to see with a 70mm scope. Get a good star chart book and pick some objects that sound interesting to you.
  7. Nov 19, 2003 #6
    Thanks Artman, And all these things ar seen without the 2x barlow or with? Would it be better to get a barlow (more versitility) or a 4mm eyepiece (better optics)? So with the 9mm and no barlow all I see are dots and with the barlow I get the polar caps on mars, and all the rest? WOW what a difference, sure wish that the scope came with a barlow!

  8. Nov 19, 2003 #7


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    Welcome to Physics Forums, jamminji! Don't worry - newbie questions are certainly welcome! Don't be daunted by some of the more complex discussions held around here.

    I don't have experience with a 70mm scope, but I suspect you could see the following...

    Mercury - point of light...maybe see its phases
    Venus - small white disk...see its phases
    Moon - great views
    Mars - small pale orange disk...maybe some shadowing...maybe a hint of an ice cap
    Jupiter - larger white disk...probably the 2 main equitorial bands and a hint of the great red spot...4 moons will appear as points of light, but they are fun to watch orbit the planet (from one night to the next or even over the course of several hours for Io)
    Saturn - small white disk with rings visible (appear as one solid ring)...moon Titan visible a good distance away
    Uranus, Neptune - points of light...tough to find unless you know what you're looking for
    Pluto - forget it

    All planets will appear small...but with patience, you should be able to pick out some details.

    Should be good for the next bright comet.

    Should be ok for seeing nebula/galaxies (will appear like faint gray clouds). Check out M42 (Orion Nebula)

    Good for star fields (check out the Milky Way).

    Good for star clusters.

    Do yourself a favor and view in an area with little light pollution.
  9. Nov 19, 2003 #8
    No Barlow necessary for nebulas, star clusters, or galaxies.

    Planets and the moon are better with a Barlow.

    I would go with the Barlow. the smallest diameter eyepiece I have is 6.5mm and I rarely even take it outside.

    Don't get your hopes up too much. 70mm is a bigger aperature than most department store scopes, but it is still small.

    I have a 4.5" f8 reflector that I was showing people Mars through and I still had to say, "You see that small white patch on the top and bottom? Those are the ice caps."

    The more you practice the better you will get at seeing the details.
  10. Nov 24, 2003 #9


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    I sympathize with your predicament. I have a 4" Newtonian reflector...one of those rickety trash scopes. I think the internal optics are decent, but the eypieces and mount both suck. I got spectacular views (and decent photos too) of the moon with it, and I could identify various maria and craters. Mars appeared as a tiny glowing disc at low power. I couldn't get it stable enough to try my higher power eyepiece. It sounds like your telescope is of decent quality, so my advice would be to persevere, and invest in some decent eypieces.When I first saw Saturn...it was amazing. I wasn't even sure at first that I had the right object, but when the rings finally came into view... definitely worth the effort and hassle (and the cold...I'm Canadian). Since I joined a local astronomy club, I've been able to see Venus and Jupiter as well (in the daytime no less) exactly as described above. So I would definitely recommend doing that.

    Double stars are easy targets for small scopes. Albireo (at the tip of Cygnus) is a great one, with wonderful colour contrast between the two stars.
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