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Stargazing Looked through a telescope for the first time

  1. Aug 25, 2004 #1

    JasonRox

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    It was great, but I only got to see the moon.

    The sky was a little cloudy, and was not close to clear. It won't be for a few weeks apparently, which sucks.

    There was also a considerable amount of wind, which kept moving the telescope.

    Another one of my problems is that my telescope camp point straight up, without tipping over. I adjust the tripod, but it's too low and it will tip. I have some ideas on fixing this, but I hoping for some tricks or experienced advice.

    I have a basic Tasco, which comes with a 4mm and 12.5 mm eyepieces. It also comes with Barlow lense, and a 1.5" erecting eyepice. I use the diagonal piece for comfort, of course.

    My range of sight is from 56x to 525x, but I only got to use 262x at most. Everything was shaking, from the winding. I wasn't adjusting or touching with my eye and it shakes. I understand why it does this, and it has been added to my long list to why wind sucks.

    I view on cement, so it's not the grass or anything.

    Another I thought was kind of funny, was that when I was viewing the moon, it kept "moving". It's kind of cool to see it all in action.

    Anyways, any help is appreciated.

    Also, I want to add again. If you know when Jupiter will be up, or Mars (so I can see the satellite rotate in 7 hours), that would be great.
     
  2. jcsd
  3. Aug 25, 2004 #2

    marcus

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    Jason I lay even odds you know this already but want to make sure.

    the first time a human measured the speed of light was in 1675 and he was timing Io, the jovian satellite.
    this is called being pedantic, there are two facts I want to make sure everybody knows which are that in 1492 columbus sailed the ocean blue and in 1675 a young dane named ole measured the speed of light
    beyond that you're on your own

    in a few minutes someone will come here and say when Jupiter will be up, or if not I will get back with that info, but a lot of people are more versed in how to be a good telescopic life-form
     
  4. Aug 25, 2004 #3

    Chronos

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    Back yard astronomy is not for the faint of heart. Trying to look straight up with an altazimuth mount is not a pretty sight, as you have discovered. Star gazing in the dead of winter should be an olympic event. It gets pretty brutal. But, there is so much to see and the very best seeing conditions cruelly tend to inversely correlate with temperature.
     
  5. Aug 25, 2004 #4

    marcus

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    here's a chunk of Jupiter ephemeris

    You can see that Jupiter is rising around 7 hours (7AM) and setting around 19:30 hourse(5:30 PM) and his Right Ascension is around 11:30 hours and his Declination is around 3 degrees north of sky equator. this is not for Canada but maybe I can find one for Canada---wouldnt be too different I'd think

    http://www.spacearchive.info/jupiterdata.htm

    what's good about this page is that you can see the whole year 2004 and find the time of year when Jupiter is in the sky at night instead of day

    23 Aug 2004 07:10:17 13:22:35 19:34:46 28.94 0.999 11h 35m 44.88s +03° 48' 09.9"
    24 Aug 2004 07:07:20 13:19:25 19:31:23 28.92 0.999 11h 36m 30.58s +03° 43' 12.6"
    25 Aug 2004 07:04:23 13:16:14 19:27:59 28.89 0.999 11h 37m 16.40s +03° 38' 14.6"
    26 Aug 2004 07:01:26 13:13:04 19:24:35 28.87 0.999 11h 38m 02.35s +03° 33' 15.7"
    27 Aug 2004 06:58:29 13:09:54 19:21:12 28.84 0.999 11h 38m 48.41s +03° 28' 16.1"
    28 Aug 2004 06:55:33 13:06:44 19:17:48 28.82 0.999 11h 39m 34.58s +03° 23' 15.8"
    29 Aug 2004 06:52:37 13:03:34 19:14:25 28.80 0.999 11h 40m 20.85s +03° 18' 14.8"
    30 Aug 2004 06:49:40 13:00:24 19:11:01 28.78 0.999 11h 41m 07.22s +03° 13' 13.2"
    31 Aug 2004 06:46:44 12:57:15 19:07:38 28.76 0.999 11h 41m 53.69s +03° 08' 11.0"
    01 Sep 2004 06:43:48 12:54:05 19:04:15 .....
     
    Last edited: Aug 25, 2004
  6. Aug 25, 2004 #5

    BobG

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    For rise/set times, try this:

    http://aa.usno.navy.mil/index.html

    Select "Data Services"

    Scroll down and select "Web Version of MICA"

    Select "Rise, Set, and Transit times"

    Enter the applicable data.

    Your longitude/latitude can be obtained from many maps, from a GPS receiver, or from:

    http://www.heavens-above.com by selecting your location from their database (Heavens-above also has astronomical data, plus satellite viewing info).

    Your offset from Greenwich Mean Time is 4 hours Atlantic Time Zone, 5 hours Eastern, 6 hours Central, etc. Subtract one hour from the offset for Daylight Savings Time.
     
  7. Aug 25, 2004 #6

    marcus

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    An idea for you

    Jason I just noticed a handy fact

    On Jan 1, 2005 Jupiter rises approximately at midnight and sets approximately at noon.

    every month that goes by it rises roughly 2 hours earlier

    so next year, by April 1, it should be rising roughyly 6 hours before midnight because 3 months will have gone by

    this is really really crude, but it is a kind of ephemeris for jupiter that one might keep in one's head instead of having to look up
     
  8. Aug 25, 2004 #7
    I'm kind of annoyed at the night sky this summer. There's nothing to look at! It was great back in spring when Venus, Saturn and Mars were all clustered together and Jupiter was way high up. Oh well...
     
  9. Aug 25, 2004 #8

    turbo

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    There's all kinds of great stuff to look at in the summer sky, you just have to be willing to switch gears. Jupiter and Saturn are really nice through a decent scope, but if you have a scope good enough to give really great planetary views, it's also quite suitable for observing globular clusters, double stars, etc. You might want to buy the 3-volume set "Burnham's Celestial Handbook". It lists all kinds of interesting objects, grouped by constellation. Those books and a good set of charts (Tirion's large-format Sky Atlas 2000.0 is nice - Uranometria 2000.0 is pricy, but goes deeper in magnitude and shows the locations of a LOT more objects) will keep you busy all summer long even if all the great-looking planets are hiding.

    Have fun!
     
  10. Aug 25, 2004 #9

    russ_watters

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    I have a great old dos program called "SkyGlobe" which prints out maps of exactly what is up and when. I recommend buying yourself a planetarium program (or downloading a free trial).

    A few tips:

    -Alt-azmuth mounts suck - it will be very difficult to keep what you are looking at sighted. Harder still to show other people. One way to avoid that is to not go overboard with the magnification.

    -Similar to above - don't go overboard with the magnification. You will quickly learn from looking at Jupiter through the 4mm gives you as much detail as through the 4mm+barlow. Higher magnification just means a larger, fuzzier picture.

    -Some nebulae are good - the one in Orion's belt shows up even with binoculars. Again, low magnification, this time because it means a brighter image.
     
  11. Aug 25, 2004 #10
    Don't knock the moon. After all, it is an alien landscape and really pretty cool. :wink:
    Although the moon is moving, what you are really noticing is the rotation of the earth turning the scope away from the moon. You will notice similar motion with the stars and planets, although the moon does seem to move faster because it is closer to us.

    Have fun with your telescope! :smile:
     
  12. Aug 25, 2004 #11
    I'm glad you have discovered how much fun amateur astronomy can be. There is a whole universe of amazingly beautiful things out there for you to see. But, a little advice; it is possible to overpower a telescope. A general rule is the maximum magnification a telescope can support is 50 times the diameter of the objective (in inches.) Beyond this power, the images will be fuzzy, and you probably will not even be able to fully focus the scope. For the 525x you quote, you would need a telescope with a 10.5 inch primary mirror (266.7mm). I don't know the size of your telescope, but I'm pretty sure it's not that big.

    It's important to understand that the purpose of a telescope is not to magnify, it's to brighten; a telescope is designed to make faint objects bright enough to see. Most astronomers of my aquaintance use very little magnification. Personally, though I have a 15 inch (381mm) scope, I have never used more than about 75x magnification.

    So, I would avoid the 525x for the best image in your scope!

    Clear Skies!
     
  13. Aug 25, 2004 #12

    JasonRox

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    Looking straight up?

    I look down into scope. The prism (I believe) bends the image up.

    The moon is great don't get me wrong at all. I was just hoping to see lots of stars. I just can't get the scope to point straight up.

    I started reading a book for beginners on building your own telescope, and I move on to an intermediate one. During that time, I will explore, and plan my telescope around what I enjoy the most.

    If I can just see the "canals" of Mars, that would be sick.
     
  14. Aug 26, 2004 #13
    Might sound silly but trying looking straight down instead... position a good mirror on the ground which captures the part of the sky you want to look at and then point and focus your telescope at the mirror. It's a popular technique used with binoculars... see here:

    http://www.tricomachine.com/skywindow/

    You don't mention what type of scope it is - refractor or reflector - but i'm assuming refractor. Also, what it is the diameter of the primary mirror/lens (it should say on the outside of the box)? As has already been mentioned, your highest practical magnification is governed by the size of the primary lens/mirror. Use low power to sweep the sky and familiarise yourself with what's up there.
     
  15. Aug 26, 2004 #14

    Phobos

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    There's a lot to explore on the moon and it's an easy target. After that, aim for the planets. This winter, get into the Orion nebula and local star clusters (also pretty easy to find). Then you'll be ready to move on to the more difficult targets.

    For now, avoid straight up. It being summer, the ecliptic (with all the interesting views of planets) should be low enough to be comfortable.

    Tough ones to start with. Consider getting a 25 mm eyepiece. It will give you a broad starfield and then once you have centered your target, you can zoom in with the 12.5. Save the 4 mm for especially clear, calm nights. With wind, forget it.

    As was said, magnification is not that important. The key is a wide aperature.


    Careful. If the cement (concrete?) is still holding a lot of heat from the day, then the temperature difference from your local air and the ambient air may blur your image. But this is probably not too significant for viewing the moon & planets. It will become significant when you move on to very faint objects.

    It is a cool reminder about all the stuff going on in the universe that we just don't think about in our normal experiences. (Like the fact that you're standing on a globe spinning at several hundred kph.)
     
  16. Aug 26, 2004 #15

    Phobos

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    Again, a broad-field eye piece will help. Then just aim toward the Milky Way or a star cluster. High magnification will reduce the number of stars you see.

    You may need to wait at least a year for a good chance at that again, due to the positions of the planets. (You'll need Mars to be closer.)
     
  17. Aug 26, 2004 #16

    turbo

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    The temperature difference (from warm surroundings or from a telescope tube or optics that have not yet arrived at ambient temperature) actually degrades point-like star images and planetary images pretty badly, and it makes finding small features on the moon very difficult. High magnification only makes the unsteady viewing worse. Finding the "faint fuzzies" is my fall-back activity when seeing is degraded. When seeing is terrible, your scope will still gather enough light to view faint objects, and it is fun to star-hop to galaxies that are "just" at (or beyond) the theoretical limits of your scope. Drop in a long focal-length eyepiece and start galaxy-hunting!
     
  18. Aug 26, 2004 #17

    JasonRox

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    I don't think it get that hot, atleast not here.

    I know that I have to wait until Mars is at its periphelion(spelling?), and Earth would be passing by. I've heard that this perfect moment has just gone by awhile ago, and won't happen for a few years, but that's fine.

    I'm not using high magnification at all. I was just sticking with the 12.5mm and 4mm eyepieces.

    As for the mirror idea, that's perfect!
     
  19. Aug 27, 2004 #18

    turbo

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    Hi, Jason:

    The temperature difference between the concrete pad and the night air doesn't have to be great to cause shimmering - trust me on this one.

    You are actually using very high magnifications, especially for an inexpensive telescope with less-than-perfect optics. To find the power you are using, simply divide the focal length of the eyepiece into the focal length of your telescope. If your telescope has a 2400mm focal length, just divide by 4mm and you'll see that you are viewing at 600X. That is far too much magnification for commercial telescopes of modest size. If you have a 4" diameter objective (mirror or lens), probably the highest practical magnification you can ever use will be about 200X (thats a 12mm eyepiece with a 2400mm objective). Keep at it - astronomy is fun.
     
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