Anonymous asked in Science & MathematicsAstronomy & Space · 9 years ago

New telescope, cold weather... is it okay?

Hey i just purchased a new refracting telescope with a 10.2 cm diameter lens. It is approximately on average -10 Celsius and i would like to know if it is safe to leave it outdoors or would that ruin it?

Would it affect the image of, say jupiter. if i kept it indoors then brought it outdoors to use.

Input and advice in using telescopes would be greatly appreciated as this is my first. Thanks!

7 Answers

  • 9 years ago
    Favorite Answer

    Well, ..., it should be absolutely fine. What can be affected more is the grease in your focuser or in the gears of it's mechanism. I actually use a Teflon based grease that resists cold weather very well.

    Over all you will get your best image when your scope reaches thermal equilibrium (same temperature as the surrounding environment) with the outside. Until, that time stars in the scope will appear to be "Blobby" and "Boily" in appearance. So an imbalance in temperature will affect the quality of your image. However, once the scope reaches thermal equilibrium stars will "Snap" right into focus and (provided that your collimation is right) resolve to fine pinpoints of light. Objects such a Jupiter will be crisply defined and cloud banding (depending on aperture size) on the planet should be readily apparent.

    -EDIT- I should note that I do a lot of cold weather observing (well maybe not as cold as those in Canada but well below freezing for sure) and it doesn't affect my scope. You, however, may want to get some decent cold weather gear Like 'wearguard' coveralls, Boots with thinsulate soles, good gloves that allow your fingers to stay nimble and dexterous yet warm and a warm hat with ear coverings. I do some of my best of serving when the night is clear, dry, and below freezing.

  • GeoffG
    Lv 7
    9 years ago

    I try to keep my telescopes in an unheated porch or garage where they are close to the outdoor temperature. This helps reduce condensation on the optics and temperature shock, which has been known to break lenses. If this isn't possible, cap the telescope before bringing it inside, so that it can warm up gradually. I tape silica gel packets in my lens caps to reduce condensation.

  • Anonymous
    9 years ago

    If you bring a cold telescope inside, moisture will condense on all the surfaces and cause fogging. It could take several hours to warm up and allow that moisture to evaporate.

    Conversely, when you take a warm telescope outside, more fogging will occur as moisture collects on the warm material.

    Most amateur astronomers leave their telescopes outside to keep the temperature stable - it needs to be protected from rain and snow, wind, etc. If you have a garage or cold room that would be best.

    Always protect the telescope with a canvas or nylon cover to keep dirt, dust, and other debris off it.

  • 9 years ago

    You can leave it out - like in unheated garage or shed, and it will stay near the ambient temp. IF you bring it in, for any reason, just leave the dust cap off.. remove the eyepiece (and or the diagonal) - until the scope has reached room temp. That way, it will dry - SAFELY.

    I keep mine in my.. 'observatory'. It is a shed that I made from kit, and fixed up the roof to roll off. I have a 12 inch sct & 6 inch refractor - they are just fine. It never gets too cool here, but the heat is extreme in summer. Today, X-mas day, it is 75 degrees.. !! YEAH..!! And clear as usual.

    Enjoy your new scope..!!!!

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  • Anonymous
    9 years ago

    Well you should keep it clean and safe from dirt,snow,rain,wind etc.But bringing it from a cold environment to a warm environment could cause it fogging up badly so my best advise is to keep it in the coldest room or place in the house to keep temperatures stable.By the way cold air and clear skies is perfect to look at the sky.

  • Anonymous
    9 years ago

    Bring it inside for sure, but cold weather is actually ideal for stargazing as long as it's clear skies.

  • 9 years ago

    I would say bring it inside!

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