How much do your skies improve (or not!) with winter?

[MarkVIIIMarc]

Tonight was probably the coolest night I had the scope out.  Its about 10 degrees C now and the sky looks like there are more stars in it than over the warm humid summer yet my limiting magnitude really isn't that different.  Maybe around just north of zenith I was catching glimpses of magnitude 4 stars where 3.5 was my previous limit.  Andromeda was still just a slightly brighter than the back ground fuzzy ball even as high as it was.

How do your skies react to winter?  It would be nice to be able to really see Pisces and find Uranus but to the south the city's light pollution makes mid 3's difficult.  Do you think I'll get some mid 4 magnitude stars for Christmas?

Thanks and clear skies to you all.

[Aaron F Johnson]

Unfortunately even though the air is thinner and thermal disturbances are reduced the light pollution you are experienceing is the predominant factor affecting your seeing. Sure you will see a slight improvement but to say it will be mag 4 stars by late December would be for you to conclude thrue observational study. And from my experience of many winters tells me they are not all created equal. Growing up under very light polluted sky's I understand your wanting peaks as there are many valleys...You can do a few things that might help your seeing but your success will be again determined by the level of light pollution you are dealing with. The two types of light pollution are atmospheric and ground level, atmospheric you can do little about but ground level is under your control. First the type of scope you are using refractor, usually built with internal baffling and a light or dew shield so essentially the only thing one can do here is extend dew shield several inches. Reflector same deal attatch a shield don't be shy a 6" reflector can handle a 12" plastic extention no problem. Flat black paint for your shield will lesson it's reflectivity but not eliminate it. Flat black only partially absorbs light and nomatter the type of scope or the price the flat black color is the same and only helps lesson reflection from ground level pollution but does not stop it. An extention shield will decrease that ground level pollution but not eliminate it either. But several small gains can equate to a medium one. Also make sure your scope isent allowing in other stray light by sealing a flashlight to the scope in a dark room if light is creeping out it's creeping in, seal it. Next is dark adaptation if all ground level light is not completely eliminated from your eyes you will be less than adapted and seeing less than you should. A black light weight cloth can be draped over you and your eyepiece achieving total dark adaptation. I spent 20 years viewing the stars in this way, best of luck with your persuit and stay warm.

[Linda]

In Autumn under a clear sky, my skies are pretty darkish and I can just see the Milkyway from my terrace. But as soon as there is snow, all lights of houses around us and green houses further away are reflected by the snow and the Milkyway is completely gone. Here in Norway, the snow doesn't melt until spring. So far it hasn't fallen at my place yet, but we are getting close. I would like to take advantage of it, if it weren't for the clouds, several weeks in a row now.

[Aaron F Johnson]

Winter is not my weather but have only noticed snow reflectivity on moonlit nights far from city lights. If the moons not up and snow reflection is canceling out your Milky Way it sounds as you are more dealing with ground level pollution and may benefit from the techniques I discribed. Best of luck with your weather Linda...

[Davesellars]

Autumn for me tends to be the worst with damp humid air causing all sorts of problems.  Once this settles down though and the temperatures starts to fall below 0 (or close to it) during the night it seems that much dryer (the air) and stable and more likelihood at least of good transparency at least getting though that first layer close to the ground.  To be honest I haven't seen any difference though in magnitude limit throughout the year - this all depends on the transparency of the air that night.  After midnight when a good amount of nearby lights have been shut off and without the Moon I can generally always see to mag 5 direct vision looking at Ursa Minor as the reference and also see the Milky Way unless the transparency is particularly bad and on really transparent nights I'm up to mag 5.3 direct vision with much more definition to the MW.

[Aaron F Johnson]

Sorry Mark for your 3 day wait for a response on your post, wish I would have noticed it sooner...Clear/Sky's Aaron...

[MarkVIIIMarc]

No problem guys, thanks for sharing your experiences.

I had not thought about snow and how bright it is.  It snows here but our weather flips reasonably fast so usually it does not stick around more than a week.  About perfect for enjoying but not getting sick of it.

The skies tonight ARE exactly the humid Autumn you were talking about Dave.  Dew is on everything, the nearby confluence of the Mississippi and Missouri rivers are fogging up the sky.  I guess Mag 3 was observable while I was rolling the trash to the curb.

Aaron, my neighbors have a couple security lights I can do without but I have a relatively large (and cheap!) lot.  I am on a street with few lights and have no neighbors to speak of across the street or in back of me so local light pollution is not the issue.  The sky, especially to the South and East has quite a bit of light pollution from the city and I suppose the oil refineries across the river.  I am hoping once the humidity falls the atmosphere will catch less of the light pollution.  We'll see, I'm not expecting miracles.