[Aavso-photometry] Possible Bottlenecks for Using a small telescope (12" Meade LX200 ) from Antarctica

[Tom Krajci]

From: "Dr.Mukund Kurtadikar" <mkurtadikar at yahoo.com>
>    What type of " transparent protection ( cover )- clear fiber/glass/quartz?" can be given to the slit to isolate the hut thermally from the the exterior atmosphere and to protect from the wind?
>   
Typically you want the telescope and dome to be at the same temperature 
as the surrounding air.  This prevents image degradation.

However a few folks have experimented with 'windows' on observatory 
structures in cold climates.  I've heard that a layer of Mylar can work 
reasonably well, with only mild image degradation from the Mylar's 
imperfections.  One source of 'optical grade' Mylar might be the same 
company that makes solar filters from Mylar:   Baader Planetarium. 

http://www.baader-planetarium.com/sofifolie/details_e.htm

Scroll to bottom 1/3 of this page and look for "*TurboFilm TM - guards 
your optics*"  This may be perfect for your situation.

You may need to remove all original lubricant/grease from the telescope 
and use low-temperature grease that does not get very viscous in 
expected low temperatures.

Focus shift from temperature change will be an issue.  You can replace 
the typical aluminum telescope tube with a material of lower thermal 
expansion.  Steel is inexpensive and easy to fabricate.  Carbon fiber is 
better, but more expensive and may be more difficult to fabricate.  (I 
found steel to be good enough for my situation on an old Celestron C-11 
- it has 1/2 the expansion of aluminum.)

Will you have to deal with frequent auroral activity that brightens the 
sky background?  Will you still take data then?  (I'm mostly curious on 
this matter...I have no practical experience.)

Feel free to contact me if you have more questions.

I hope this helps,
Tom Krajci

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Tom Krajci
Cloudcroft, New Mexico
http://picasaweb.google.com/tom.krajci

http://overton2.tamu.edu/aset/krajci/

Center for Backyard Astrophysics (CBA)
http://cbastro.org/ CBA New Mexico

American Association of Variable Star
Observers (AAVSO): KTC http://www.aavso.org/
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