Desperately Seeking Darker Skies.

[Mamsoth]

Hello all, I wondered if I might pose a small question in the hope of finally being able to venture from my heavily light polluted back garden into some darker skies for the first time ever!!!

I live in Orpington which is a large suburb about 20km SE of London, my skies are a deep red on the bortle scale (Urban/Suburban Transition) and my NELM is roughly 4.8 around the zenith.

Using this Light Pollution map...

http://avex.org.free.fr/cartes-pl/uk/UK-pl-relief-topo.html

I found an area called Cudham which has yellow/green skies. It is only 6km from my home (as the crow flies). my question then is as follows...

Is it at least possible that yellow/green skies could exist mere 6km away from a brightly lit suburb and 30km from a major city?

It is 6km of countryside, but I would have thought the LP that was present in my skies would carry for well over 6km, even if there isn't much local light pollution generated within that 6km distance.

In a nutshell I would have thought that even a small village like Cudham that has minimal light pollution in a 10km area around itself would find it's night skies were still swamped by the bigger suburbs that surround it.

I'd just go and check it out myself but as I don't drive it may be a while before I can get there with my telescope so I'd appreciate any help or insight on how far LP can travel and whether anybody perhaps has any good dark site reccomendations preferably in or around the Kent area.

Thanks a bunch and Clear Skies To You

[Bizibilder]

It all depends on the "lie of the land". A hill or valley position can make all the difference to LP as well as straight line distance from the source.

[Euan]

That's a very nice and detailed map, but I wouldn't expect it to be as accurate as it is detailed

I compared it to a place I know further north that is noticeably better than where I live and it's on the same scale, so obviously the way this is extrapolated there are loads of other factors that come into play

The best way to find out is to go there, you won't get an accurate answer otherwise

[Mamsoth]

I did wonder whether the map was probably a little too good to be true, I will stroll down to the site and suss it out, even if it offers only a slight improvement over my washed out skies I will consider it a triumph. Thanx for the replies : )

[Moonshane]

according to the LP map I live in a magenta area which is pretty terrible.

I agree completely with the line of sight point as I observe around the back of my house and it's really quite dark. luckily I face East and the worst LP is NW and W of my location - maybe a little to the S so my position is as good as it gets locally. that said, I can see Beehive and Andromeda with the necked eye (whatever that is!! - see yellow on the map) and have rarely failed a serious attempt to find a messier object on a decent observing night. so, what I am saying is, do try and observe from home too as you will probably be surprised what you can see. I am not sure how long you have been observing of course so this last comment may be ridiculous.

I am also hoping to get to a dark site soon and either the peak district, north wales of maybe around NE Preston might be good (I live near Stockport).

[Mamsoth]

I am envious Shane, I've never been able to make out andromeda with my naked eye alone. Sounds like you're skies are a little better than mine.

Although I did post this in beginners help & advice I have actually been avidly observing for a couple of years, I just thought it might be best posted here as I've got a beginners grasp of the effects of light pollution, as Ive never ventured out of the light trap that is my back garden boohoo, lol.

If you do make it to a dark site I'd be interested to hear how you got on, I have only managed to locate galaxies with a SB of about 13th magnitude with my 12" Dob and so my mind boggles as to the possibilities under a truly dark sky.

Anyways, Cheers for the reply and happy StarGazing

[Moonshane]

cheers and I agree a dark site would be awesome.

that said, and you have more experience than me so I am probably wrong but I think seeing galaxies with a magnitude of 13 is really pretty impressive?

[ollypenrice]

If there is an astrosoc near you they will know the dark sites and someone will be sure to give you a lift out there as well.

Olly

[Mamsoth]

cheers and I agree a dark site would be awesome.

that said, and you have more experience than me so I am probably wrong but I think seeing galaxies with a magnitude of 13 is really pretty impressive?

I'm not really sure if 13th mag is good going or not tbh Shane, I'm never sure whether the limits of what i can detect are due to the LP or down to my observing skills.

Because none of my mates are even remotely into astronomy I never get to compare observations and build up a realistic picture of the limits of observability from my area.