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Mars Watch: Where is the Red Planet Now?

  1. Aug 18, 2003 #1

    Ivan Seeking

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  2. jcsd
  3. Aug 19, 2003 #2
    I've been keeping my eye on mars, watching it through my telescopes. Even now, at only moderate magnification, I can make out the glow on the edge of the disk of the polar ice caps. It's going to be great. They say at only 75x magnification it will look as big as the moon does to the naked eye!

    Even for those who don't know anything about astronomy, it is very easy to find. In the Northern Hemisphere, watch the path that the moon has been following (across the Southern sky) and it will be near that (except that it will rise before the moon does) and look like a bright orange star rising over the East horizon of North America at about 10:30 (slightly earlier each night). Until the moon rises it will be the brightest thing in the night sky.
  4. Aug 20, 2003 #3
    I've been having a look at it
    every night the past couple weeks
    just with the naked eye. It is
    as bright as Venus usually is but
    has the faint reddish tint.

    Considering what Artman said it
    sounds like it might be a worth-
    while investment to get a tele-
  5. Aug 20, 2003 #4
    A telescope is a worthwile investment to some people (I have 6 myself) , but you should evaluate your interest before investing in one.

    If you think you are more than mildly interested, don't buy a "trash scope." The type sold in department stores for less than $100.00 with aperatures of 60mm for refractors and 80mm for reflectors and .965" eyepieces. These scopes claim high magnification, (which they cannot resolve), are cheap, difficult to focus, have poor finderscopes, sometimes plastic optics, very little eye relief in the eyepieces and are generally not a very good investment.

    The most important thing is aperture. This is what determines how much you will be able to see, how much light your scope can gather.

    For a first telescope that can grow with you, I recommend either a 80mm or 90mm refractor f5 for star patterns, f8 or higher for planets and the moon.

    Or a 114mm or 150mm Dobsonian or equatorial mount reflector. These are generally about f6 to f8 and are good for all around viewing.

    The 114mm Dob. is probably the ideal first scope. It can resolve up to 273x magnification and can show several galaxies and all of the Messier Objects and can be purchased from a decent manufacturer for about $200.00.

    I also recommend a red dot finder, 1.25" eyepieces in at least two sizes (25mm and 10mm are decent) and a good 2x or 3x Barlow (the barlow doubles or triples the magnification of any eyepiece).

    Sorry about the lengthy response, but a lot of people get really frustrated with astronomy because of poor equipment, when for a few bucks more they can get a decent starter scope that they can enjoy for years.

    Here are the names of some of the less expensive, high quality scope manufacturers: Orion, Celestron, and Meade.
  6. Aug 21, 2003 #5

    Thanks for the rundown. Info like
    this is PhysicsForums at its best.

    I was actually thinking along the
    lines that any old telescope would
    be better than the naked eye so
    it is good that you warned me this
    woudn't be the case.

    I'm definitly not into it enough
    to spend $200. for the minmum
    good one. Armed with your info,
    though, I might do some looking
    for a used one. I get the urge
    to peer up now and then when some-
    thing like this is going on. Last
    time it was a lunar eclipse that
    made me wish I had a telescope.

  7. Aug 21, 2003 #6

    There is an inexpensive alternative. Build one yourself. Dobsonian mounted telescopes can be made for less than $100.00 fairly easily. Ebay has cheap mirrors for telescopes. You can get a 4.5" (114mm) telescope mirror for about $10 plus shipping. This price is about 1/4 of the price you find elsewhere, the catch is that these are 1/4 wave and that should be the total for the entire optical system, so you need a high quality secondary mirror, 1/10 wave or better, and decent eyepieces. Add another $10-$15 for a 1.5" secondary mirror (Orion sells these in 1/10 wave or better) and buy some hardware for the mirror cell, and diagonal, pickup some eyepieces from Surplus Shed and you can have a decent telescope for less than $100 and a few hours time.

    There are sites all over the internet that show instructions for building one.

    Here's one:
    http://www.glpbooks.com/oyb/roscope/focuser.html [Broken]

    You could build a 70mm refractor (not too bad, better than the department store 60mm models) using a 70mm objective lens, a 1.25" focuser and 1.25" star diagonal and a couple of eyepieces for about as little as $60.00 from Surplus Shed (great surplus internet store, lots of great deals on optics and cheap shipping).

    Check them out here: http://www.surplusshed.com/

    Let me know if this sounds interesting to you I can help you find more infomation on the process.

    I've built two reflectors, a 6" (150mm) and a 4.5" (114mm) and a copier scope (only 60mm, but with a short focal length so it is much better than a trash scope) that I threw together for only about $40. (The copier scope is excellent for it's size at star viewing because it has such a short focal length, but is not great for the moon or planets. Good travel scope though as it is only about 12" long and attaches to a photo tripod).
    Last edited by a moderator: May 1, 2017
  8. Aug 22, 2003 #7

    Thanks for the idea and the leads
    to sources. It may come to that.

    Actually what I have in mind is
    to keep my eye open at the big
    weekend swap meet (or flea market
    as they may call them where you
    live) for something in the range
    of what you reccomended as decent.

    I went today and a guy had a
    scope he was asking $40.00 for.
    He said it was $150.00 brand
    new so I figure it actually cost
    him $100.00. I could probably
    have talked him down to $30.00
    but thanks to you, I realized it
    wasn't a decent scope.

    I will just keep going and be on
    the lookout. It is quite a large
    swap meet and is held every week-
    end. I've frequently noticed
    telescopes there. It's a common
    thing to be able to buy stuff in
    decent shape for a quarter of the original price.

    What is a Dobsonian mount, by the way?

  9. Aug 26, 2003 #8
    i have been wathcing it too and it pisses me off

    on one lense it was clear to see but small and you couldent see much detail but with a 3x barlow it was nice and close up but i needed to focus it....But noooo mars had to be a butt face and slowly move away, anyone eles have this problem?
  10. Aug 27, 2003 #9
    Actually, Celestron has received praise for its quality, but very well priced 60mm and other small telescopes.

    A starter could consider some binoculars. It is easy to use, and will give a close view, and it is very comfortable on the eyes. I prefer it for quick viewing over my telescope.
  11. Aug 27, 2003 #10


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    Don't feel bad...Mars is notorious for being difficult in revealing clear details. When it's closest, it tends to kick up global dust storms. When it's farthest, it looks very small in 'scopes. The details of the surface are easily blurred by the Earth's atmosphere.

    Typical. For telescopes, aperature is key and magnification is secondary. After all, when you magnify a blurry image, you magnify the blur too!

    You mean aside from the rotation of the Earth?
  12. Aug 27, 2003 #11
    Hi Kenikov,
    I agree with you that Celestron's 60mm is not a bad little scope. It has quality optics and has a 1.25" star diagonal that uses 1.25" eyepieces. The eyepices it comes with are within the resolving range of the scope. This is not the case with the "trash scopes" I was talking about.

    I also agree with you about the Binoculars, but for planets they are not very good. That is why I was pushing telescopes. Binoculars are an excellent starting point for astronomy and very useful for seasoned astronomers.

    Yup. This is the problem with even a good 60mm scope. 30% less light gathering capability than a 80mm and 55% less than a 114mm just not enough light to resolve the details of the image.

    Dust storms are a problem especially this close to the Sun, but I was watching it last night in my 114(mm) scope with decent seeing conditions at about 200x magnification and I could see Mars' South pole ice cap and several dark patches that I could probably (If you put a gun to my head :smile: ) match to satelite photo images of land features. So I think, so far that the dust storms haven't started yet.
    Last edited: Aug 29, 2003
  13. Aug 28, 2003 #12


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  14. Aug 29, 2003 #13
    That highly frustrated me my first time I was viewing celestial objects.. It was highly annoying, especially since my altazimuth's mount for vertical was very difficult to set still.

    I left my telescope for awhile since it got annoying and I got frustrated. Plus, my Science teacher told me to keep both eyes opened when viewing and that was extremely difficult to do and it started hurting my eyes, so I just cover one eye with a hand now.

    I've gotten use to it now though.

    I think I know what you mean about 60MM telescopes and their problems.

    I was looking at mars, and I only saw a black and white yellow circle. Hopefully this wasn't because I was aiming it at some tree or something else completely unrelated to mars , but I think it was mars.

    I just saw the surface, and black/white, greyish type colour. Even with my strongest lens + 2x Barlow nothing changed besides magnification.

    How about Bushnell? They make some pretty nice optical tools.

    zoobyshoe, I believe Celestron Firstscopes are under $200, and so are some Bushnells, including Reflectors.
    Last edited: Aug 29, 2003
  15. Aug 29, 2003 #14
    Bushnell is kind of hard to place. They do make some decent optical instruments. Their telescopes get mixed reviews from users. They are usually priced very reasonably and you can get a good one, however, I hear that you can also get a poor one. This is true of most of the manufacturers though.

    Last night I had a Mars Party a bunch of people came over to view the planet. A friend brought a Meade 60mm scope for me to look at. It came with several pieces of equipment that included items that ranged from useless to dangerous to use. It had a 3x Barlow, which was useless except maybe looking at the moon, a 4.5 mm lens useless except for the moon, and a solar eyepiece filter which is dangerous NEVER USE A SOLAR EYEPIECE FILTER!!!! If you want to view the sun, project it onto a piece of white cardboard or use a full objective filter. The scope also came with a 25mm eyepiece and a 12.5mm eyepiece both of which worked very well and gave a nice sharp image.

    One of the most important things is a nice smooth mount. A telescope isn't much use if you can't get the object into the field of view and keep it there. This is often where the cheaper scopes like Bushnell cut corners to keep their price down, so just be careful with these.
  16. Aug 29, 2003 #15


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    I viewed it last night (8/28)...also with a 114mm scope...and I could see the south polar ice cap and an faintly dark patch below that (inverted image of course). A couple days ago, I had a clearer view of the darker patch.
  17. Aug 29, 2003 #16
    I came close to buying a very, very well priced reflector scope from Bushnell, at Gart Sports. It actually had a very nice aluminum stand, large aperture and looked pretty nice.

    There were complications though. Afterwards, I found the Celestron Firstscope 60MM though, and they looked nice and was from a good company. Too bad it came with a wooden stand though :( and I don't have the money to replace it.
  18. Sep 1, 2003 #17
    It's been putting on quite a show, hasn't it Phobos? :smile:

    On Wednesady 27th it was a little hazy where I was watching it, but the details were actually enhanced. I think because the glare was reduced a little. Those faint dark patches showed up nicely.
  19. Sep 9, 2003 #18
    Don't feel bad...Mars is notorious for being difficult in revealing clear details. When it's closest, it tends to kick up global dust storms. When it's farthest, it looks very small in 'scopes. The details of the surface are easily blurred by the Earth's atmosphere.

    yea well since that post i decude to make my dream to travel to mars to kick it in it's face (no pun inteaded) mars is almsot as bad as the sun it seems like an amzing place but it wont let you see it.
  20. Nov 16, 2003 #19

    I've been thinking about scopes again.

    I do not understand what the f number refers to. Is it better to have high or low f numbers?

    Also, what do different eyepieces do. You recomended a 25 and a 10, and also 2x and 3x barlow lenses.

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