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APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 4:11 am
by APOD Robot
Red Sprite Lightning over the Andes
Explanation: What are those red filaments in the sky? They are a rarely seen form of lightning confirmed only about 30 years ago:
red sprites. Recent 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 earlier this year from
Las Campanas observatory in
Chile over the
Andes Mountains in
Argentina.
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 Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 4:23 am
by jks
Wow, a stunning image!
Also, please note that the Discuss link points to the APOD of March 28.
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 4:40 am
by Ann
jks wrote: ↑Tue Mar 30, 2021 4:23 am
Wow, a stunning image!
Also,
please note that the Discuss link points to the APOD of March 28.
Yes, please note that!
Today's APOD is indeed stunning. But me being the way I am, I remembered that red sprites are supposedly related to some blue stuff, namely blue jets.
The picture at right shows a red sprite that is connected to a blue jet. The Gemini Observatory picture looks quite different than the APOD, because in the Gemini image the red sprite seems to "collimate" into a blue-white flash of lightning that hits a cloud bank below it.
In the APOD there are no clouds below the red sprites, and they don't collimate into narrow jets. Also there are barely any hints of blue in the lower parts of the jets.
Well, whatever the reason for the different appearance of in the red sprites in the APOD and the red sprite in the Gemini image, the APOD is indeed stunning.
Ann
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 8:04 am
by RocketRon
The clouds and thunderstorms could be behind (below) that line of hills. ?
You'd have to imagine that the air would be rather thin at that altitude of ~ 80 kms.
The mechanism that fires up these things is going to be interesting, if/when it is resolved....
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 8:12 am
by wolfie138
damn, that looks like something from a sci-fi film. stonking image.
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 10:09 am
by Johanos
The (beautifull) featured pic is from 2020 , not 2021.
![:) :ssmile:](./images/smilies/smile.gif)
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 11:19 am
by De58te
The featured image was taken earlier this year. If that is so then why does the featured image Instagram link have a date of January 9, 2020?
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 11:24 am
by Indigo_Sunrise
Also, please note that the Discuss link points to the APOD of March 28.
x2.
The clouds and thunderstorms could be behind (below) that line of hills. ?
Yes, that's what Mr. Beletsky describes on his instagram page, where this image was first posted - in January of
2020, as user Johanos pointed out.
Very interesting image
![Cool 8-)](./images/smilies/icon_cool.gif)
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 12:34 pm
by orin stepanek
Wow! What an amazing piece of electricity!
![Shocked :shock:](./images/smilies/icon_eek.gif)
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 7:50 pm
by johnnydeep
Yes, very cool image. One question: both the text and the WikiPedia article say that:
sprites are actually clusters of small, decameter-sized (10–100 m or 33–328 ft) balls of ionization that are launched at an altitude of about 80 km (50 mi) and then move downward at speeds of up to ten percent the speed of light, followed a few milliseconds later by a separate set of upward moving balls of ionization.
So, are we seeing both the downward moving balls of ionization AND the smaller upward moving balls here?
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 8:18 pm
by Chris Peterson
johnnydeep wrote: ↑Tue Mar 30, 2021 7:50 pm
Yes, very cool image. One question: both the text and the WikiPedia article say that:
sprites are actually clusters of small, decameter-sized (10–100 m or 33–328 ft) balls of ionization that are launched at an altitude of about 80 km (50 mi) and then move downward at speeds of up to ten percent the speed of light, followed a few milliseconds later by a separate set of upward moving balls of ionization.
So, are we seeing both the downward moving balls of ionization AND the smaller upward moving balls here?
As this is a long exposure (seconds or tens of seconds) of a phenomenon that lasts no more than milliseconds or tens of milliseconds, then yes... we're seeing the entire sequence beginning to end, both directions, captured in a single frame.
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 8:37 pm
by johnnydeep
Chris Peterson wrote: ↑Tue Mar 30, 2021 8:18 pm
johnnydeep wrote: ↑Tue Mar 30, 2021 7:50 pm
Yes, very cool image. One question: both the text and the WikiPedia article say that:
sprites are actually clusters of small, decameter-sized (10–100 m or 33–328 ft) balls of ionization that are launched at an altitude of about 80 km (50 mi) and then move downward at speeds of up to ten percent the speed of light, followed a few milliseconds later by a separate set of upward moving balls of ionization.
So, are we seeing both the downward moving balls of ionization AND the smaller upward moving balls here?
As this is a long exposure (seconds or tens of seconds) of a phenomenon that lasts no more than milliseconds or tens of milliseconds, then yes... we're seeing the entire sequence beginning to end, both directions, captured in a single frame.
Makes sense. But do we know how long the exposure is? I couldn't find it stated anywhere. Also, I did follow one of the links to
https://www.flickr.com/photos/pennstate ... 17/sizes/l, which shows multiple entire sprites forming within the span of a single millisecond:
This would mean that the entire scene of the APOD could
potentially be only a few milliseconds, no?
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 9:19 pm
by Chris Peterson
johnnydeep wrote: ↑Tue Mar 30, 2021 8:37 pm
Chris Peterson wrote: ↑Tue Mar 30, 2021 8:18 pm
johnnydeep wrote: ↑Tue Mar 30, 2021 7:50 pm
Yes, very cool image. One question: both the text and the WikiPedia article say that:
So, are we seeing both the downward moving balls of ionization AND the smaller upward moving balls here?
As this is a long exposure (seconds or tens of seconds) of a phenomenon that lasts no more than milliseconds or tens of milliseconds, then yes... we're seeing the entire sequence beginning to end, both directions, captured in a single frame.
Makes sense. But do we know how long the exposure is? I couldn't find it stated anywhere. Also, I did follow one of the links to
https://www.flickr.com/photos/pennstate ... 17/sizes/l, which shows multiple entire sprites forming within the span of a single millisecond:
This would mean that the entire scene of the APOD could
potentially be only a few milliseconds, no?
I didn't find the exposure length. But it was clearly taken with an ordinary commercial digital camera, and I have enough experience taking nighttime images with that kind of equipment to know that we're looking at an exposure time on the order of 10 seconds. Those submillisecond images required image intensifiers and other exotic equipment.
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 10:50 pm
by johnnydeep
Chris Peterson wrote: ↑Tue Mar 30, 2021 9:19 pm
johnnydeep wrote: ↑Tue Mar 30, 2021 8:37 pm
Chris Peterson wrote: ↑Tue Mar 30, 2021 8:18 pm
As this is a long exposure (seconds or tens of seconds) of a phenomenon that lasts no more than milliseconds or tens of milliseconds, then yes... we're seeing the entire sequence beginning to end, both directions, captured in a single frame.
Makes sense. But do we know how long the exposure is? I couldn't find it stated anywhere. Also, I did follow one of the links to
https://www.flickr.com/photos/pennstate ... 17/sizes/l, which shows multiple entire sprites forming within the span of a single millisecond:
This would mean that the entire scene of the APOD could
potentially be only a few milliseconds, no?
I didn't find the exposure length. But it was clearly taken with an ordinary commercial digital camera, and I have enough experience taking nighttime images with that kind of equipment to know that we're looking at an exposure time on the order of 10 seconds. Those submillisecond images required image intensifiers and other exotic equipment.
So, would that mean the sprites have a long life after forming and look very much the same over several seconds? (Though the millisecond sequence pic shows that multiple sprites can indeed form and evolve very quickly.) Or are the sprites very short lived, and we are only seeing multiple sprites in the APOD pic merely because multiple ones have come and gone during the (long) exposure?
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Tue Mar 30, 2021 11:28 pm
by Chris Peterson
johnnydeep wrote: ↑Tue Mar 30, 2021 10:50 pm
Chris Peterson wrote: ↑Tue Mar 30, 2021 9:19 pm
johnnydeep wrote: ↑Tue Mar 30, 2021 8:37 pm
Makes sense. But do we know how long the exposure is? I couldn't find it stated anywhere. Also, I did follow one of the links to
https://www.flickr.com/photos/pennstate ... 17/sizes/l, which shows multiple entire sprites forming within the span of a single millisecond:
This would mean that the entire scene of the APOD could
potentially be only a few milliseconds, no?
I didn't find the exposure length. But it was clearly taken with an ordinary commercial digital camera, and I have enough experience taking nighttime images with that kind of equipment to know that we're looking at an exposure time on the order of 10 seconds. Those submillisecond images required image intensifiers and other exotic equipment.
So, would that mean the sprites have a long life after forming and look very much the same over several seconds? (Though the millisecond sequence pic shows that multiple sprites can indeed form and evolve very quickly.) Or are the sprites very short lived, and we are only seeing multiple sprites in the APOD pic merely because multiple ones have come and gone during the (long) exposure?
I don't know if the individual sprites were nearly simultaneous or separated by several seconds. But they are, individually, short lived.
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Wed Mar 31, 2021 3:03 am
by Fred the Cat
Our global search for
strange phenomena is wandering
closer to the universe’s most
common matter.
The whimsical
dark quark?
![Wink :wink:](./images/smilies/icon_wink.gif)
Re: APOD: Red Sprite Lightning over the Andes (2021 Mar 30)
Posted: Wed Mar 31, 2021 8:43 am
by mdione
Just a geographic/redaction nitpick:
The featured image was taken earlier this year from Las Campanas observatory in Chile over the Andes Mountains in Argentina
I would remove the 'in Argentina' thing since it's confusing: The Andes are
the boundary between Chile and Argentina, and if the obs is in the Chilean side, why reference Argentina at all? I'm asking as an Argentinian...
![Smile :)](./images/smilies/icon_smile.gif)