Newbie questions... with a twist

Hello all,
first of all I only have a general knowledge of astronomy (the money I saved for two years for a
telescope when I was a teenager went into a computer instead, 25 years ago).

I'm going to be in Dome C for the coming year. In short: middle of Antarctica, 3200m altitude, no
wind, completely flat, complete darkness for 4 months, winter temperature down to -84C (-120F) !!!

In other words, perfect observation conditions, except for the cold. And nothing else to do (no
internet connexion !)

So, as a complete newbie I'd like some equipment recommendations for $500 to $1000:
- telescope
- accessories
- software (I already have Celestia)
- Nikon mount for camera
- advice
- ???

Taking into account the cold, I wonder if there are any telescopes with integrated CCDs you can
just leave outside and control and display from inside !!!


For more info on Dome C, check out my site:
http://www.gdargaud.net/Antarctica/DomeC.html
http://www.gdargaud.net/Antarctica/Concordia.html

Thanks
--
Guillaume Dargaud
http://www.gdargaud.net/
"If at first you don't succeed, destroy all evidence you tried."

While reading in the bathroom on Sat, 25 Sep 2004 18:40:57 +0200, I
saw that "Guillaume Dargaud" had written:

Taking into account the cold...

Does glass shrink in extreme cold? Would a lens shrink at the same
rate as the metal tube? Does glass become brittle the way plastic
does in extreme cold? How much plastic is going to be in your setup?
At what temp do any adhesives in your setup fail? At what temp can you
expect trouble from the lubricant? I can think of dozens of similar
questions to ask, that no one in North America normally has to
consider but that you do.

In short, for your needs, I very strongly doubt you're going to get a
dependable instrument in your stated price range.

--------------
Beady's Corollary to Occam's Razor: "The likeliest explanation of any phenomenon is almost always the most boring one imaginable."


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snip
500 to 1000 is not nearly enough to set yourself up with a remote CCD
setup.
;-)

/snip

Tell me about it.

Meade LX90 £1800
Sony VAIO £1400
TuCam Pro £80
Skymap Pro II £80
85Ah Lead Acid battery £30

Cables to tie all the stuff together £150 sounds alot, but that does include
a Dew Heater.

Of course, I'm not including other toy's like, eyepieces, filters, camera,
wedge.

AAAAAAAAAAAAAAGGGGGGGGGGGGGHHHHHHHHHHHHHHH So that's where all my money's
gone for the past two years! he he.

Regards

Colin Dawson
www.cjdawson.com

Answering everybody at once:

- yes, resistor networks are a good idea, I'm using some already for scientific gear. But due
itself is only a problem when going back indoors. The air is so dry outside that there is no
condensation (strangely there is a bit of reverse sublimation on some plastics)

- weight is not a huge issue. I already take several TONS of scientific equipment with me (I'll be
in charge of at least 6 different experiments). I can squeeze 15kg or so of telescope.

- power is no issue. I can run a wire from the station. I guess I may even be able to use it
through a roof (open) window, not sure about the building's vibrations though.

Meade announced a new inexpensive CCD imager (Meade DSI) with software for
$300.00. It's high speed USB2, that connected to a NexStar 5 would be a
nice combination.
Would that be the "$994.95 Nexstar 5i 5.0"/127mm Schmidt-Cassegrain Telescope (1250mm f/10.0)
with Motorized Altazimuth Mount, Nexstar Computerized Hand Controller, 25mm (50x) 1.25" Eyepiece,
Finderscope & Tripod " ? Can the hand controller be replaced by a PC cable control ?

Sorry to ask very basic newbie questions, but I'm currently very busy preparing the expedition and
if experienced astros can do my homework for me, I'll be glad: what accessories would go with that
for an interesting setup ? Sun/Moon filter (are there different kinds ?!?) What kind of eyepiece
(if any with the imager) ? Anything else besides an astronomy textbook ? I guess I'll have time to
read the basics once there !


Since IR astronomy is one of the big selling points of doing it in Antarctica (with the 'seeing'),
is there anything I could be doing there that's hard/impossible to do in the rest of the world ?

BTW, here are two series of comments about Dome C telescopes, past trials and future projects:
http://science.slashdot.org/article..../09/15/1953249
http://science.slashdot.org/article..../09/19/1811222


Does glass shrink in extreme cold? Would a lens shrink at the same
rate as the metal tube? Does glass become brittle the way plastic
does in extreme cold? How much plastic is going to be in your setup?
At what temp do any adhesives in your setup fail? At what temp can you
expect trouble from the lubricant? I can think of dozens of similar
questions to ask, that no one in North America normally has to
consider but that you do.

I have no idea on the quality on construction of those equipments. Maybe someone from Alaska can
give me more info... I'd go for something without too much glass to minimize risks. I must say
that I used my Nikons 35mm (F801s and F100) extensively at -50C without any trouble.

Thanks all
--
Guillaume Dargaud
http://www.gdargaud.net/
"There are three kinds of lies: lies, damned lies, and statistics." - Disraeli (1804-81),
British statesman.

"Guillaume Dargaud" wrote in message
...
Hello all,
first of all I only have a general knowledge of astronomy

snip

And yet you are going to Dome C?

Amongst all your Googling, have you seen this FAQ?

http://www.phys.unsw.edu.au/nature/

John Beaderstadt wrote in message . ..
While reading in the bathroom on Sat, 25 Sep 2004 18:40:57 +0200, I
saw that "Guillaume Dargaud" had written:

Taking into account the cold...

Does glass shrink in extreme cold? Would a lens shrink at the same
rate as the metal tube? Does glass become brittle the way plastic
does in extreme cold? How much plastic is going to be in your setup?
At what temp do any adhesives in your setup fail? At what temp can you
expect trouble from the lubricant? I can think of dozens of similar
questions to ask, that no one in North America normally has to
consider but that you do.

In short, for your needs, I very strongly doubt you're going to get a
dependable instrument in your stated price range.

It doesn't have to be that cold for things to become nearly
impossible. Even the simplest flexible cabling could become a
nightmare. Standard PVC sheathed mains cable becomes like stiff steel
fence wire at only -15C. I know became I have to coil up my mains
extension cable out to the telescope after an observing session.
Sometimes it's simply impossible and has to stay out there until
things warm up a bit. Locally we rarely go below -18-22C. But I don't
bother with drive power when it's that cold.

Observing can be difficult too. Touching metal with your bare skin is
like getting burnt. It really hurts that much! (I dont like gloves at
the telescope if I can avoid it) You won't want your eye (or side of
your nose) near something very cold either. I rotate my few eyepieces
constantly through my down jacket and waistcoat pockets and the
focussing mount. Just to keep them frost free. Otherwise they dew up
immediately with the proximity of my eye. (I've learnt to breathe
through my left ear ;-)) Getting them cold means eyepieces 'steam up'
inside too! That takes overnight R&R time indoors to clear. Even
wooden and plastic boxes don't protect my eyepieces from condensation
in use on the coldest nights.

Perhaps they use some sort of lubricant around the eyepiece to protect
the observer during surveying and binocular use at the Poles? Or
perhaps decent rubber eyeshields do that job well enough? Be aware
that some cheaper eyepieces have artificial rubber eyeshield which
quickly stiffen in the cold. Then the eyeshield falls off as a useless
ring severed at the usual fold-back point. I wouldn't hold out much
hope for any plastic components in the proposed Polar Telescope. Early
polar explorers quickly discovered that even metals lose their
strength in low temperatures.

Most batteries quickly lose their power in the cold I believe.

Chris.B

first of all I only have a general knowledge of astronomy
And yet you are going to Dome C?
Well, I'm doing atmosphere physics there (I already have at least 6 large experiments to run).
I'm actually a computer guy.

Amongst all your Googling, have you seen this FAQ?
http://www.phys.unsw.edu.au/nature/
Yes, and I've been in contact with the author, but he's not running in the same league...
They hope to have funding for a 2m telecope at Dome C for 2006.
--
Guillaume Dargaud
http://www.gdargaud.net/
"Teamwork is essential; it allows you to blame someone else."

"Guillaume Dargaud" wrote in message ...

I'm going to be in Dome C for the coming year. In short: middle
of Antarctica, 3200m altitude, no wind, completely flat, complete
darkness for 4 months, winter temperature down to -84C (-120F) !!!
...
So, as a complete newbie I'd like some equipment recommendations ...

First of all, none of us is qualified to answer that question.

Second, I would be very surprised if *any* commercially available
equipment will work. Any devotee of polar exploration literature
knows that machinery is famous for breaking down at low temperatures.
Conventional lubricants become worthless; different materials contract
at different rates, so that parts that fit together at normal temps
either jam or fail to make contact.

Imagine the temps going the other way. The difference in temp between
room temp and the South Pole is *less* than the difference between
room temp and boiling. How much astro equipment would work at 100C?

- Tony Flanders

On 26 Sep 2004 04:17:39 -0700, (Tony Flanders)
wrote:

First of all, none of us is qualified to answer that question.

The OP would probably do better consulting with experienced polar
scientists than with amateur astronomers. The temperature aspect
would have a greater effect on equipment choice than any of the
conventional astronomical aspects.

Second, I would be very surprised if *any* commercially available
equipment will work. Any devotee of polar exploration literature
knows that machinery is famous for breaking down at low temperatures.
Conventional lubricants become worthless; different materials contract
at different rates, so that parts that fit together at normal temps
either jam or fail to make contact.

I've seen first hand how a temperature of minus 30 F has totally
incapacitated a commercially built, unmodified, Schmidt Cassegrain
Telescope. Typical power cables became inflexible -- actually, a
sodered connection 'snapped' inside my drive controller. The RA knob
snapped off when I attempted (unsuccessfully) to move the scope in RA.

I've used homemade, manually driven, alt-az mounted scopes in the
minus 20 to minus 30 F range without any mechanical difficulties. I
prefer a solid-tubed Newtonian for the low temperatures I've
experienced; but many commercially built Newtonians rely on glue of
one form or another to attach the secondary mirror to a secondary
holder. I would *expect* the glue bond to snap and fail at
sufficiently low temperatures. Bottom line: The scope should be
designed (or at least modified) specifically for cold weather use.

One last story: The lowest temperature at which I've made an
astronomical observation and sketch was minus 50 F. I used a pair of
20x80 binoculars on a homemade alt-az mount. I set the arrangement up
on my front porch, pointed the binoculars at a bright comet, started a
sketch, reached up to fine tune the focus -- and discovered that in
those few minutes the focusing mechanism had frozen solid. It was
impossible to make any further focusing adjustment. Fortunately the
focus was good enough as it was. I completed the sketch and quickly
brought everything back inside. The binoculars were probably outside
for only 15 minutes or so.

My suggestion: A solid-tubed Newtonian with mirror cells that hold
the optics semi-firmly, but not very tightly. As for mount and drive
motors or anything electronic or motorized -- I would suggest
consulting with experienced polar scientists. Minus 120 F is too far
removed from my personal experience -- besides, my preference is to
avoid motors and electronics at low temperatures; but you'll probably
want motors, electronics, and computer control in order to collect
data while you drink hot chocolate from within the comfort of a heated
structure ;-)

Sketcher
To sketch is to see.

Sorry to ask very basic newbie questions, but I'm currently very busy
preparing the expedition and
if experienced astros can do my homework for me, I'll be glad: I guess I'll
have time to read the basics once there !

Now that you have a good idea what observing will involve from there, I
thought you might like some amateur celestial treasures to hunt down once
you're set-up:
http://www.astroleague.org/al/obsclu.../ssbinoc2.html
They all rock thru binos or a scope.

Happy hunting,
SSX