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APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 4:05 am
by APOD Robot
Red Sprite Lightning over the Czech Republic
Explanation: What are those red filaments in the sky? They are a rarely seen form of
lightning confirmed only about 35 years ago:
red sprites. Research
has shown that following a powerful positive
cloud-to-ground lightning strike,
red sprites may start as 100-meter balls of
ionized air that shoot down from about 80-km high at 10 percent the
speed of light. They are
quickly followed by a group of upward streaking ionized balls. The
featured image was taken late last month from the
Jeseniky Mountains in northern
Moravia in the
Czech Republic. The distance to the
red sprites is about 200 kilometers.
Red sprites take only a
fraction of a second to occur and are best seen when
powerful thunderstorms are visible from the side.
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 5:24 am
by RocketRon
Amazing photo !
How long was the exposure ?
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 6:59 am
by david@gordon.fm
What's the structure that appears to be on fire in the lower RH corner?
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 9:14 am
by Iksarfighter
30 sec exposure ? As the stars moved a bit.
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 9:41 am
by VictorBorun
Iksarfighter wrote: ↑Mon Sep 12, 2022 9:14 am
30 sec exposure ? As the stars moved a bit.
I think the stars were smeared by camera vibration during 100 ms exposure and the sprites lasted 1 ms and did not smear so much.
The sprites are tracks of cold plasma balls that go up at 10% speed of light and therefore those balls do get smeared in a 100 ms exposure:
it takes (90 km - 50 km)/(30 km/ms) = 1.3 ms for a ball to travel its track
It seems very strange to me that a cold plasma ball going up should fork 3 ways to make a trident.
By the way
Rorik of Dorestad, the Danish prince to start the Rurikid dynasty, used both Thor's hammer and trident insignia (that trident survives at the modern Ukranian flag). Must been a red sprite trident, to go together with Thor
Update. Sorry, Rorik used bident; the Rurikid made it into a trident later, after Olga (Helga) added Freya's hawk-flying cloak and it transformed to a middle prong.
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 12:08 pm
by heehaw
Absolutely REMARKABLE photo!
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 12:20 pm
by JohnD
10% light speed? Wow! A quick Google finds that to be 67 MILLION mph. They are ionised gas, in the upper atmosphere, so not very dense. Can anyone estimate their mass? Because to accelerate from zero to that, even for a millisecond, must use a heck of a lot of energy, even for a packet of thin gas!
John
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 12:38 pm
by mtbdudex
Epic capture, from his facebook page
"Selection of the best elves from the night of 26.8.2022 over the north of Bohemia. Photographed by the Golden Mountains. Sony A7S modified + 135GM, ISO 2500, F/2, 3.2s"
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 12:42 pm
by VictorBorun
JohnD wrote: ↑Mon Sep 12, 2022 12:20 pm
10% light speed? Wow! A quick Google finds that to be 67 MILLION mph. They are ionised gas, in the upper atmosphere, so not very dense. Can anyone estimate their mass? Because to accelerate from zero to that, even for a millisecond, must use a heck of a lot of energy, even for a packet of thin gas!
John
the air does not move; some free electrons move, but not all the way: they shift here and there. It's the cold plasma red fluorescence zone that is moving.
Like waving a laser beam, this non-material movement is massless
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 12:52 pm
by VictorBorun
mtbdudex wrote: ↑Mon Sep 12, 2022 12:38 pm
Epic capture, from his facebook page
"Selection of the best elves from the night of 26.8.2022 over the north of Bohemia. Photographed by the Golden Mountains. Sony A7S modified + 135GM, ISO 2500, F/2, 3.2s"
3 seconds exposure? My guess was wrong. Still, that
is too short to smear stars by daily rotation
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 12:54 pm
by orin stepanek
Red sprites; like fireworks in the Czech Republic skys!
beautiful; almost looks like a sifi scene!
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 1:01 pm
by Chris Peterson
VictorBorun wrote: ↑Mon Sep 12, 2022 12:52 pm
mtbdudex wrote: ↑Mon Sep 12, 2022 12:38 pm
Epic capture, from his facebook page
"Selection of the best elves from the night of 26.8.2022 over the north of Bohemia. Photographed by the Golden Mountains. Sony A7S modified + 135GM, ISO 2500, F/2, 3.2s"
3 seconds exposure? My guess was wrong. Still, that
is too short to smear stars by daily rotation
"Selection".
This is a stack of individual 3-second images, taken over an unspecified period. So we'd certainly expect to see star trails.
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 3:26 pm
by JohnD
VictorBorun wrote: ↑Mon Sep 12, 2022 12:42 pm
JohnD wrote: ↑Mon Sep 12, 2022 12:20 pm
10% light speed? Wow! A quick Google finds that to be 67 MILLION mph. They are ionised gas, in the upper atmosphere, so not very dense. Can anyone estimate their mass? Because to accelerate from zero to that, even for a millisecond, must use a heck of a lot of energy, even for a packet of thin gas!
John
the air does not move; some free electrons move, but not all the way: they shift here and there. It's the cold plasma red fluorescence zone that is moving.
Like waving a laser beam, this non-material movement is massless
Thank you, Victor! So, this is more like a charge moving through the atmosphere? Like lightning, but about 250 times FASTER?
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 5:23 pm
by Jim Armstrong
It was not too long ago that photographs of this wonderful phenomenon were nearly nonexistent.
Look at them now, with every expectation of more!
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 9:21 pm
by Sa Ji Tario
david@gordon.fm wrote: ↑Mon Sep 12, 2022 6:59 am
What's the structure that appears to be on fire in the lower RH corner?
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 9:22 pm
by Sa Ji Tario
Sa Ji Tario wrote: ↑Mon Sep 12, 2022 9:21 pm
david@gordon.fm wrote: ↑Mon Sep 12, 2022 6:59 am
What's the structure that appears to be on fire in the lower RH corner?
communications tower
Re: APOD: Red Sprite Lightning over the Czech... (2022 Sep 12)
Posted: Mon Sep 12, 2022 11:18 pm
by DonB312
Jim Armstrong wrote: ↑Mon Sep 12, 2022 5:23 pm
It was not too long ago that photographs of this wonderful phenomenon were nearly nonexistent.
Look at them now, with every expectation of more!
I was thinking exactly this too. Especially as I was clicking the many links in today's APOD.
I love that technology is always improving while at the same time becoming in reach of more and more people; both amateur and professional. I think we live in a wonderful time for learning about our universe.
- Don