Bicon Sky Fun
Had a great time at Bicon in Bradford last weekend. Thanks to the organising team and everyone else who contributed to the event. Much fun, good people to talk to, interesting talks, and excellent curry. I had possibly the best Masala Dosa I've ever had at the Prashad which was an 8 minute stroll from the venue.
Even better, we took baby steps as a community towards being a bit less sucky on race. There is a long way to travel, but we are at least now moving in a more positive direction.
The whole thing was bookended for me by impressive sky phenomena.
The most spectacular was the sun dogs I saw from the M1 near Barnsley on the way there, at about 8pm on 9th August.
The 'common' name is sun dogs; the technical name is parhelia. I put 'common' in quotes because hardly anyone sees them - me included, until now.
I'd wanted to see one since I was about 16 when I found out they existed, and even more since I was about 25 when a physicist friend gave me his copy of Minnaert's 'Light and Colour in the Outdoors' which talks about many such phenomena. If you're remotely interested in this sort of thing, and find equations in books helpful rather than hateful, I very thoroughly recommend it.
There's the 22-degree halo (circle of white/yellow light round the sun) that I've seen before, though not as often as Minnaert reckons it's visible - he thinks they're readily observable one day out of four, or one out of two if it's April/May, and on up to 200 days a year if you are a good observer. I've seen it a handful of times, but I've seen far more 22 degree halos around the moon. I think they occur with similar frequency around the sun and moon, but I see the lunar ones much more often because if the moon is out, I almost always look at it lots. So I'll see a moon halo pretty much any time I'm out of doors at a time where there is one. (About half the time you look at the moon and there are any clouds at all you can see the lovely coloured corona right next to it, which is lovely, and the moon is just nice to look at anyway.) But I almost never look at the sun while it's out - or indeed at the part of the sky it's in - for obvious reasons. Come to think of it, when I deliberately choose which direction to look in the sky relative to the sun, it's to face the antisolar point (the point you'd get if you draw a line from the sun through your eye and out the other side the same distance) to look for rainbows.
So I'd only ever seen hints of sun dogs / parhelia before.
This was something else. It was unmistakably something interesting and brightly coloured in the sky, and clearly parhelia if you knew anything about them.
It was fantastic! I was shouting and laughing as I drove along.
There were two bright spots in the sky, at the same height as the sun (quite low in the sky), and pretty much spot on 22 degrees away from the sun. (Bit less than outstretched thumb-to-finger at arm's length.) Later (looking up my Minnaert) I learned that they were probably more like 23 degrees - parhelia are just outside the 22 degree circle, and are further away from it the lower the sun is in the sky.
Each spot was about 2 degrees wide (could cover with outstretched thumb, just, but not finger) and about 10-15 degrees tall. The inside bit nearest the sun was red, grading through to bluish at the outer edge. The red/yellow/green colours were particularly vivid; the blue was a bit washed out and subtle. No sign of arcs or rings, although the sun appeared as a bright white/yellow pillar even taller than the sundogs. The one on the right was taller and brighter than the one on the left, although that was partly the way the land lay.
I thought about pulling over on to the hard shoulder to see it better and get snaps, but decided not to - hard shoulders are desperately dangerous places and you don't want to be there unless you really have to. I came off at the next junction and found an A-road layby nearby, but the view wasn't half so good and my phone's camera shots only show a slightly brighter patch in the clouds - and then only if you look closely. I managed to navigate back to the motorway and the view was great again.
Having looked up other people's photos since, I think this was one of the more spectacular displays that ever happen: these were brighter, more colourful, and bigger than in most photos. There weren't the exciting rings, halos and arcs you get in many photos, but the colour and intensity were stunning.
I saw it for about 20 minutes to half an hour altogether, along the M62 as well. It faded as the sun set. Stupendous, and something I'll remember for a long long time.
Then later - about 10pm - I got a lovely view of the International Space Station from the area just outside the bar. And saw it again from the same place around the same time on the last night (Sunday). Not quite so rare and hard to see, but wonderful nonetheless.
This entry crossposted to http://doug.dreamwidth.org/245492.html, where there are
comment(s) not shown here.
Even better, we took baby steps as a community towards being a bit less sucky on race. There is a long way to travel, but we are at least now moving in a more positive direction.
The whole thing was bookended for me by impressive sky phenomena.
The most spectacular was the sun dogs I saw from the M1 near Barnsley on the way there, at about 8pm on 9th August.
The 'common' name is sun dogs; the technical name is parhelia. I put 'common' in quotes because hardly anyone sees them - me included, until now.
I'd wanted to see one since I was about 16 when I found out they existed, and even more since I was about 25 when a physicist friend gave me his copy of Minnaert's 'Light and Colour in the Outdoors' which talks about many such phenomena. If you're remotely interested in this sort of thing, and find equations in books helpful rather than hateful, I very thoroughly recommend it.
There's the 22-degree halo (circle of white/yellow light round the sun) that I've seen before, though not as often as Minnaert reckons it's visible - he thinks they're readily observable one day out of four, or one out of two if it's April/May, and on up to 200 days a year if you are a good observer. I've seen it a handful of times, but I've seen far more 22 degree halos around the moon. I think they occur with similar frequency around the sun and moon, but I see the lunar ones much more often because if the moon is out, I almost always look at it lots. So I'll see a moon halo pretty much any time I'm out of doors at a time where there is one. (About half the time you look at the moon and there are any clouds at all you can see the lovely coloured corona right next to it, which is lovely, and the moon is just nice to look at anyway.) But I almost never look at the sun while it's out - or indeed at the part of the sky it's in - for obvious reasons. Come to think of it, when I deliberately choose which direction to look in the sky relative to the sun, it's to face the antisolar point (the point you'd get if you draw a line from the sun through your eye and out the other side the same distance) to look for rainbows.
So I'd only ever seen hints of sun dogs / parhelia before.
This was something else. It was unmistakably something interesting and brightly coloured in the sky, and clearly parhelia if you knew anything about them.
It was fantastic! I was shouting and laughing as I drove along.
There were two bright spots in the sky, at the same height as the sun (quite low in the sky), and pretty much spot on 22 degrees away from the sun. (Bit less than outstretched thumb-to-finger at arm's length.) Later (looking up my Minnaert) I learned that they were probably more like 23 degrees - parhelia are just outside the 22 degree circle, and are further away from it the lower the sun is in the sky.
Each spot was about 2 degrees wide (could cover with outstretched thumb, just, but not finger) and about 10-15 degrees tall. The inside bit nearest the sun was red, grading through to bluish at the outer edge. The red/yellow/green colours were particularly vivid; the blue was a bit washed out and subtle. No sign of arcs or rings, although the sun appeared as a bright white/yellow pillar even taller than the sundogs. The one on the right was taller and brighter than the one on the left, although that was partly the way the land lay.
I thought about pulling over on to the hard shoulder to see it better and get snaps, but decided not to - hard shoulders are desperately dangerous places and you don't want to be there unless you really have to. I came off at the next junction and found an A-road layby nearby, but the view wasn't half so good and my phone's camera shots only show a slightly brighter patch in the clouds - and then only if you look closely. I managed to navigate back to the motorway and the view was great again.
Having looked up other people's photos since, I think this was one of the more spectacular displays that ever happen: these were brighter, more colourful, and bigger than in most photos. There weren't the exciting rings, halos and arcs you get in many photos, but the colour and intensity were stunning.
I saw it for about 20 minutes to half an hour altogether, along the M62 as well. It faded as the sun set. Stupendous, and something I'll remember for a long long time.
Then later - about 10pm - I got a lovely view of the International Space Station from the area just outside the bar. And saw it again from the same place around the same time on the last night (Sunday). Not quite so rare and hard to see, but wonderful nonetheless.
This entry crossposted to http://doug.dreamwidth.org/245492.html, where there are
comment(s) not shown here.