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Worth buying telescope?

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  1. Aug 21, 2014 #1
    I'm unable to see any stars or anything in general besides the moon when looking at the sky. This might be due to the light pollution as the actual pollution levels is very low. Is it worth buying a telescope here? Will I even be able to see anything in the sky like Mars or anything similiar? Stars? Or will it be completely dark everytime I try to watch?
     
  2. jcsd
  3. Aug 21, 2014 #2
    cool. so where do live so that you can't see any stars in the sky?
     
  4. Aug 21, 2014 #3
    I live in Gothenburgh, Sweden. More precisely, Hjällbo in Gothenburg...
     
  5. Aug 21, 2014 #4

    Drakkith

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    Inside the city the light pollution will prevent you from see "deep sky" objects, such as nebulas and galaxies, but the moon and all the planets can easily be seen. Just be aware that you will not be seeing detail like you see in most of the pictures you see of the planets unless you have a BIG telescope and extremely good "seeing" (quality of the air turbulence that the light has to go through).

    However, I think that it's well worth it to grab a small scope that you can afford to see the planets, as they are amazing views even if you can't see a lot of detail. There's something about seeing them in person that an image can never replicate.
     
  6. Aug 21, 2014 #5
    Ok, thanks! But how do I know the location of the space stuff?
     
  7. Aug 21, 2014 #6

    davenn

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    Stellarium is one excellent and free piece of planetarium software for
    finding the planets and deep space objects ( galaxies, nebulae, star clusters etc)

    As far as living in a city and using a telescope .... you just have to do what I and many others do
    put the scope in the car and drive to a dark site so that you can see the faint objects :smile:

    I have to drive for the best part of an hour to get away from the city skyglow

    cheers
    Dave
     
  8. Aug 21, 2014 #7

    Chronos

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    I would suggest a nice binocular for starters. It will also be handy for terrestrial viewing so you're not sinking money into a limited use item like a telescope. If you find that sufficiently entertaining you always have the option of upgrading your collection to include a telescope. The bino aperture should be 50 mm and 10x or less magnification - and preferably less. I like the Nikon Pro 7x50. It runs about $250 US. There are, however, other 7x50 binos available and many are quite inexpensive. I generally prefer to spend a little extra money up front to avoid disappointment. Rest assured a quality telescope is going to cost well over $250 unless you get lucky on a used one. Star charts are readily available, including on the net, to assist in locating celestial objects.
     
  9. Aug 22, 2014 #8

    collinsmark

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    By the way, just to be clear regarding the planets, you should be able to Venus, Mars, Jupiter and Saturn (and even Mercury if you catch it at the right time of its orbit) with your naked eyes alone -- no binoculars or telescope required.

    This of course assumes that it's not cloudy, and the planet in question is presently on this side of the night sky. If the planet you are looking for is not on this side of the sky at the moment, it probably will be eventually if you wait until morning (unless its angular position is right next to the Sun). Planets rise and set just like the moon and the Sun (well, almost "just like." 'Slightly different timing, but only slightly).

    You should be able to see the planets with your naked eye even in the most light-polluted cities in the world. These planets are really bright (compared to other celestial objects besides the Sun and Moon).

    The easiest way to spot them if you don't know what to look for, and if you have a smart phone, is to download an app such as Google Sky Map (for Android -- there are other, similar apps for the iPhone). Just point your smartphone at the sky, and it shows you what's what.

    Another option is to use a astronomy, computer program like davenn mentioned.

    Baring those, here is some general advice:
    • Planets do not twinkle like stars do. If you see a stationary, star-like thing but it's not twinkling like the rest (and it's on the ecliptic -- see below), it's likely a planet. The reason stars twinkle is because even with huge optical telescopes with incredible magnification, they still appear very point like, and are thus subject to even the tiniest atmospheric aberrations, as the light passes through the Earth's atmosphere. Planets on the other hand, although subject to the same atmospheric aberrations, have a much larger angular size, from our perceptive. By that I mean when viewed with a telescope, the planet looks like a disk, not a point. So when viewed with the naked eye, the atmospheric aberrations tend to be averaged across the disk, eliminating the "twinkle."
    • Planets follow a path along what is called the ecliptic. This is the same general path through the sky the Sun moves through. The ecliptic extends more-or-less from East to West and is tilted toward the South, since you are in the Northern hemisphere. The amount of "tilt" also depends on the time of year. The ecliptic will extend higher in the night sky during the winter months and lower (more toward the South) in the summer months. (That's related to, yet effectively opposite, the reason the sun is higher in the sky during the summer and lower in the sky during the winter.)
    • Venus and Mercury (especially Mercury) will never stray too far from the Sun. Venus will always be either in the West after sunset or in the East before sunrise. For example, you will never see Venus in the East just after sunset. The same applies to Mercury, but to a greater extent. It's actually pretty tough to spot Mercury only because it is always so close to the Sun.

    By all that, I mean to say that you don't need a telescope or binoculars to see the planets and figure out where they are. [Edit: Except for Uranus and Neptune -- you'll need binoculars or a telescope for those. But the rest you should be able to spot with the naked eye.]

    But a telescope, even a small, inexpensive telescope, can allow you to see details on the planets, such as the four Galilean moons of Jupiter, the rings of Saturn, the phases of Venus (yes, Venus has phases, not dissimilar to that of our Moon), possibly ice caps on Mars (don't hold your breath on that, but if you catch Mars at opposition you might have a good chance), and the craters on the Moon.

    [Edit: and since you have a comparatively high latitude in Gothenburg, Sweden, the ecliptic will be tilted quite a bit to the South. So, when planet hunting, pick a location that doesn't have a lot of obstructions (trees, buildings, etc.) when looking South.]
     
    Last edited: Aug 22, 2014
  10. Aug 23, 2014 #9

    Vanadium 50

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    I'm going to disagree a bit with that. Yes, this often is the case, but it's not always true - I don't know what the greatest elongation of Mercury is, but it's well over 20 degrees. I think the real problem, particularly in urban areas, is that visible Mercury is always low on the horizon.

    I just looked online, and on the 21st of September Mercury reaches maximum elongation. It also happens to be right next to Spica, so it should be easy for people to spot. (Mercury will be thr brighter one) I would say the best shot is about 30 minutes after sunset - earlier and the sky will be bright, and later the planet will be low.
     
  11. Aug 23, 2014 #10

    collinsmark

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    'Fair enough. :smile:
     
  12. Aug 23, 2014 #11

    Drakkith

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    I'm going to side with Collinsmark on this one. Even at maximum elongation, the early morning/late evening twilight tends to drown out Mercury and make it difficult to find. At least for me.
     
  13. Aug 23, 2014 #12
    A telescope is worth it even if you can only see the moon! Go crater spotting... try and find the locations of the moon landers...

    You can certainly see the sun, project the sun's image onto a piece of paper (don't look directly at the Sun! That means instant blindness...) Spot those sun spots...

    In any case, you must be able to see some stars. I can't imagine the light pollution is so bad that you can't ever see anything! Try and keep street lamp out of centre if your field of vision, look out for stars & planets, however faint. Turn a telescope on those objects, and see them better!

    The moons of Jupiter are great fun - plot them and work out their orbits, and try and work out which one is which.

    Track down Messier objects, and double stars. Find out when meteor storms are heading your way. Any comets approaching?

    A telescope will let you see bits of the milky way through the light pollution.

    Infuriate your parents/significant-other by continuously dragging them into the cold to see the latest Marvel. "I know it's -5, but you gotta see Saturn's rings!"

    So much to do! Get binoculars as well, a wider vision is sometimes better, even with lower magnification.
     
  14. Aug 23, 2014 #13

    davenn

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    But be warned on this advice .... and even severely stopping the light down before entering the scope, you WILL possibly still burn out the optics ( damaging mirrors, lenses, eyepieces)

    DONT DO THIS WITH OUT A PROPER FULL APERTURE SOLAR FILTER


    I cannot stress that strongly enough

    Dave
     
  15. Aug 23, 2014 #14

    Chronos

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    Agreed davenn, a full aperture filter is best for solar viewing, but, this is probably beyond the scope of the OP.
     
  16. Aug 24, 2014 #15

    George Jones

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    Yes, I have seen Mercury several times, including, from latitude 45, in the conjunction

    https://www.physicsforums.com/showthread.php?p=2022576#post2022576

    I doesn't look like this is going to be a favourable elongation for viewing Mercury. Better will be elongation viewable in the eastern dawn sky on November 1.

    http://in-the-sky.org/newsindex.php?feed=innerplanets

    gives observing conditions.

    I now live at latitude 54, which makes the angle worse. The above link gives

    "will be 0° below the horizon at dusk" on Sept. 21 at my latitude;

    "it will appear no higher than 11° above the horizon." on Nov. 1 at my latitude;

    "it will appear no higher than 5° above the horizon." on Sept. 21 at New York City's latitude;

    "it will appear no higher than 13° above the horizon." on No.v 1 at my New York City's latitude.
     
  17. Aug 24, 2014 #16

    AlephZero

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    From my latitude (about 53N) there is no particular problem seeming Mercury with the naked eye, given a reasonably "level" horizon and not too much air pollution. (Note, air pollution, not light pollution.) But it's not remarkable enough to make anybody ask themselves "what's that?"

    When all 5 naked-eye planets were visible in the evening sky in March 2004, I could easily see Mercury from my office window along with the other four, looking straight into the light pollution of a city with population 125,000.
     
  18. Aug 25, 2014 #17
    I second this advice. Years ago I bought an inexpensive celestron 12x60 binocular and have nearly worn them out. Any time we have an after dark cookout or campfire in the neighborhood, out come the binos. Since they are inexpensive I don't worry about sharing with children and people are always amazed to see Jupiter and some of the moons.

    The best telescope is the one you will use.
     
  19. Aug 26, 2014 #18
    Do you have a car? If so, throw it in the trunk and drive out 30min and you should be good to go :)
     
  20. Aug 27, 2014 #19

    Bobbywhy

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    Here is a fine map of world-wide light pollution. It doesn't tell you where to find all the "space stuff" but it does tell you where are the dark skise nearby you.

    http://djlorenz.github.io/astronomy/lp2006/

    Good stargazing! Bobbywhy
     
  21. Sep 1, 2014 #20
    I think it is really just a matter of letting your eyes adjust. There are more people per square mile here than any place in the US outside of New York City, and you can still see plenty of stars on a clear night. Through a 12" scope, you can see deep sky objects.

    Sure, the light pollution is pretty bad, but even in New York you can still see the Summer Triangle and enough of the brightest stars to find major asterisms even if Casiopia is not quite a W and the hunter left to spear Leo and leaving only his belt for you to see.
     
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