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strongmanmike
06-11-2019, 06:14 AM
I just came across This PHOTO (https://www.flickr.com/photos/hiroc/48993225143/in/gallery-158811181@N07-72157711314205072/) by Hisayoshi Kato and it made me reminisce my recent experience under true dark skies.

After nearly 40 years involved in astronomy, astrophotography and observing, I only very recently finally observed all the features captured in Kato's image and which had previously only been myths. At the end of August/start of Sept this year, I was spending 4 days at a mates observatory 3hrs drive west of Cairns, out in the savannahs of far northern Queensland Australia. The skies out there are black and genuine Bortle 1 with an SQM of 22+. The Gegenschein was easy to see, like a faint but obvious ball shaped patch, as was the fainter zodiacal bridge that connects the Gegenschein to the Milky Way and the Eastern horizon and visible in Katos photo....it was truly spectacular. It was like having two Milky Way's in the sky at once, a bright one and a faint one perpendicular to it! Early each night, when the centre of the Milky Way was overhead, it lit up our observing pad like a night light and our bodies and hands etc cast very obvious shadows and the Zodiacal light in the west at the start of each evening extended right up to the Milky Way and was so bright that we avoided observing galaxies in Virgo for fear of them being washed out! It is truly spectacular when you are under genuine perfect dark skies!...something that many people never get to see...it took me until age 52 to finally witness it.

Another excellent shot by Petr Horaleck (http://www.astronom.cz/horalek/wp-content/uploads/2016/05/2016_04_14_La_Silla_From_Gegen_to_F alse_Dawn_1600px-1.png) shows well what it all looked like overhead to my eyes!...minus the colour in the Milky Way of course....it was truly spectacular and something I will never forget.

Thanks Tim :prey2:

h0ughy
06-11-2019, 07:42 AM
I have experienced this at astrofest a couple of times in the evening and in the morning and even took a photo of the sdm showing 22.06
Being more north it would indeed be brighter. It was something I have never seen before and eventually it became a regular thing to see every year I go. That and satellites and meteors....

strongmanmike
06-11-2019, 11:04 AM
...yet another reason to finally get to an Astrofest! :thumbsup:

Mike

graham.hobart
06-11-2019, 12:27 PM
Wow! (from bortle 6 skies ) this is amazing

AnakChan
06-11-2019, 02:04 PM
The only time I experienced Bortle 1 skies was in the 90s when I was working in Olympic Dam. That’s when I bought my Vixen VC200L from Claude when he was a Vixen distributor.

Beautiful pix by Kato-san.

strongmanmike
06-11-2019, 02:59 PM
These days you'd have to travel at least 50km from Olympic Dam to get under true dark skies and then you would still see its light dome, it has a light pollution footprint larger than Broken Hill, a town of nearly 20,000 people! :eyepop:...mines definitely don't use smart lighting at night....:mad2:

Mike

AnakChan
06-11-2019, 03:05 PM
Yikes, the population has trippled since then and just checking on lightpollutionmap now, there's more pollution than Coober Peddy :-(.

ausastronomer
08-11-2019, 04:30 PM
The best skies I have experienced are on the West Coast of the South Island of New Zealand. Because it so rugged, a lot of places are difficult to access and there are very few people live there. In addition to the dark skies, the skies are very transparent because there is no dust particulate in the air. The area from Wanaka to Franz Joseph Glacier encompassing Mount Aspiring National Park and Mount Cook National Park are exceptionally dark. Unfortunately due to the mountainous topography, the seeing can be pretty ordinary and more conducive to naked eye and binocular observing than telescopic observing. If you can get up high enough above the thermals from the adjacent mountains the seeing can be very good and sub 1". Unfortunately the very few roads to get you to this altitude are very hairy and these points more often than not can only be reached by chopper due to heart failure, snow and or rock falls.

Cheers
John B

Paul Haese
08-11-2019, 07:47 PM
We've (those in SA) now got an IDA approved International Dark Sky Reserve just two hours from Adelaide. Sky measurements were done with professional grade sky measurements by DSTG personnel. SQM's were initally used by the IDA said the 22.0+ measurements were not recognised, so some specialised techniques were used to measure the sky. Measurements ranging from 21.9 to 22.06 (Although the IDA says above 22 is not possible, I know it is myself). So those skies are considered to be Bortle 1. Certainly we have seen the bridge with our own eyes in the pristine conditions out there. For more information take a look for the River Murray International Dark Sky Reserve (the word International has only been added this week with the IDA gold standard approval).

multiweb
08-11-2019, 08:04 PM
I remember seeing the Gegenschein at coonabarabran once. The milkyway was wrapped around the horizon. I actually saw it and asked what it was to Lachlan who was observing with some Texans.