What to do when it's -20 or colder...

By Cathy Hall

Having done quite a number of cold sessions over the years, I wanted to emphasize - especially to newbies - that <not> going out in -30C is not 'wimping out'. In fact, it is quite prudent.

If you are dressed properly, I have found that observing all night at about -20C (with no wind) can be quite enjoyable. What is appropriate attire? Something along the lines of the following: full long johns, then a 'polar plus' layer top and bottom, then a down parka and fully lined snow pants... wool socks, coupled with boots rated to at least -20C (if you put in -40C liners) that have lots of toe wiggle room... very carefully chosen arctic gloves, or several pairs of mittens... and a wool balaclava with parka hood overtop. Add a couple hand warmer units for your pockets. That will be sufficient in -20C.

If the windchill drives it colder than that, then it is not really recommended to go out. Exceptions include - observing from inside an observatory where you are sheltered from the wind, or observing with some sort of a wind shield to really block the wind.

If no shelter is available, and the windchill is -30C or worse, you better have a darn good reason for going out - as you are risking a variety of things such as frostbite, drive battery failure and dew heater failure for your scope, and car problems. There better be a meteor storm, or a deluge of lunar impacts, or a comet impacting Jupiter, or the best auroral storm of the decade, or a supernova, or another Comet Hyakutake. Actually, there are probably a number of reasons to go out at -30C... but you get the idea.

What are other options? Well... if you're really feeling photon-deprived on a bitterly cold night, try observing out your window. Don't laugh. Comets have been found by persons looking out windows. Now... it helps if you have an unfrosted window.. and single pane windows are better, less bending of the light. But... you can, in a pinch, look at planets out the window, and the moon, and you can do lots of variable star estimates out the window... and you can see comets, and satellites, and the International Space Station...

Anyway... just wanted to comment. Enjoy your observing - but be careful out there!