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APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 4:06 am
by APOD Robot
Star Trails and Lightning over the Pyrenees
Explanation: The beauty in this image comes in layers. On the bottom layer is the picturesque village of
Manlleu in
Barcelona,
Spain. The
six-minute exposure makes car lights into streaks. The next layer is a mountain --
Serra de Bellmunt -- of Europe's famous
Pyrenees. Next up is a
tremendous lightning storm emanating from a classically-shaped
anvil cloud. The long exposure allowed for the capture of many intricate
lightning bolts. Finally, at the top and furthest in the distance are
stars. Here, the multi-minute exposure made stars into
trails. The trailing effect is caused by the rotation of the Earth, and the
curvature of the trails indicates their distance from the
north spin pole of the Earth above. Taken after sunset in early June, the
lightning storm soon moved off. The stars, though, will continue to
circle the pole for as long as the
Earth spins -- surely billions of years
into the future.
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 4:44 am
by Ann
That's a magnificent portrait of a ferocious storm and its torrent of lightning bolts.
That said, and this APOD being considered an image more suitable for an APOD than an
EPOD, I have to say that star trail pictures drive me slightly crazy. That is because I think I should be able to identify the stars, and I try, and I almost think I can do it
, but then I never can.
I get defeated every time.
It's like being shown a picture of a
galaxy and being told in the caption that this is a "galaxy", a generic specimen, and that is all you need to know. (Actually, the galaxy I gave you a link to is IC 342.)
Can anyone help me with today's APOD? Can someone out there identify any of the stars behind the star trails in this image?
Ann
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 5:21 am
by Rauf
"The stars, though, will continue to circle the poll for as long as the Earth spins"
I am sorry, but is that supposed to be poll?? Shouldn't it be pole instead??
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 5:23 am
by owlice
Rauf wrote: ↑Mon Sep 19, 2022 5:21 am
"The stars, though, will continue to circle the
poll for as long as the Earth spins"
I am sorry, but is that supposed to be poll?? Shouldn't it be pole instead??
Yes, I think so, and I've corrected it here and on FB and dropped a note to the APOD editor.
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 5:37 am
by Rauf
Ann wrote: ↑Mon Sep 19, 2022 4:44 am
That's a magnificent portrait of a ferocious storm and its torrent of lightning bolts.
That said, and this APOD being considered an image more suitable for an APOD than an
EPOD, I have to say that star trail pictures drive me slightly crazy. That is because I think I should be able to identify the stars, and I try, and I almost think I can do it
, but then I never can.
I get defeated every time.
It's like being shown a picture of a
galaxy and being told in the caption that this is a "galaxy", a generic specimen, and that is all you need to know. (Actually, the galaxy I gave you a link to is IC 342.)
Can anyone help me with today's APOD? Can someone out there identify any of the stars behind the star trails in this image?
Ann
The mountain is to the north and northwest of the Manlleu city. This picture was taken on June 9, after sunset. I tried recreating the scene in Stellarium and the only bright constellation that matched the star trails were stars of Cassiopeia. I am not sure how if fits though..
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 5:38 am
by Rauf
owlice wrote: ↑Mon Sep 19, 2022 5:23 am
Rauf wrote: ↑Mon Sep 19, 2022 5:21 am
"The stars, though, will continue to circle the
poll for as long as the Earth spins"
I am sorry, but is that supposed to be poll?? Shouldn't it be pole instead??
Yes, I think so, and I've corrected it here and on FB and dropped a note to the APOD editor.
Thank you
I was just wondering what does poll means here
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 6:23 am
by FLPhotoCatcher
Was this a single exposure, or is it a composite?
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 8:01 am
by Ann
Rauf wrote: ↑Mon Sep 19, 2022 5:37 am
Ann wrote: ↑Mon Sep 19, 2022 4:44 am
That's a magnificent portrait of a ferocious storm and its torrent of lightning bolts.
That said, and this APOD being considered an image more suitable for an APOD than an
EPOD, I have to say that star trail pictures drive me slightly crazy. That is because I think I should be able to identify the stars, and I try, and I almost think I can do it
, but then I never can.
I get defeated every time.
It's like being shown a picture of a
galaxy and being told in the caption that this is a "galaxy", a generic specimen, and that is all you need to know. (Actually, the galaxy I gave you a link to is IC 342.)
Can anyone help me with today's APOD? Can someone out there identify any of the stars behind the star trails in this image?
Ann
The mountain is to the north and northwest of the Manlleu city. This picture was taken on June 9, after sunset. I tried recreating the scene in Stellarium and the only bright constellation that matched the star trails were stars of Cassiopeia. I am not sure how if fits though..
Thanks, Rauf! I was actually thinking of Cassiopeia myself. That long bright blue streak at top made me think of
Gamma Cas, but as for the rest of the constellation... I can't find it there.
Ann
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 1:47 pm
by RJN
Rauf wrote: ↑Mon Sep 19, 2022 5:21 am
"The stars, though, will continue to circle the
poll for as long as the Earth spins"
I am sorry, but is that supposed to be poll?? Shouldn't it be pole instead??
Oops. My bad. Fixed it.Thanks! I apologize for the mistake.
- RJN
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 2:03 pm
by orin stepanek
Beautiful storm cloud photo! Too bad that they're so scary! Best to
be indoors during lightning!
Kitty scared; don't like thunder and lightning!
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 2:16 pm
by Chris Peterson
FLPhotoCatcher wrote: ↑Mon Sep 19, 2022 6:23 am
Was this a single exposure, or is it a composite?
Almost certainly a stack of shorter images. Uncooled cameras cannot take such long exposures without dark current saturating their sensors.
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 2:16 pm
by Chris Peterson
Rauf wrote: ↑Mon Sep 19, 2022 5:21 am
"The stars, though, will continue to circle the
poll for as long as the Earth spins"
I am sorry, but is that supposed to be poll?? Shouldn't it be pole instead??
A completely understandable Freudian slip during American election season...
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 4:38 pm
by MarkBour
The art of circling a poll.
RE: Circling the pole for billions of years, and being able to recognize which stars are which from the tracks.
Martin Vargic has created a nice plot of some favorites, including Cassiopeia:
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 5:14 pm
by MarkBour
Ann wrote: ↑Mon Sep 19, 2022 4:44 am
I have to say that star trail pictures drive me slightly crazy. That is because I think I should be able to identify the stars, and I try, and I almost think I can do it
, but then I never can.
I get defeated every time.
Ann
Okay, I opened the image in Photoshop and made a new layer, putting a dot at the far left of each trail. When finished with that, I inserted a black mask in an intermediate layer. I immediately realized that there's lots of information I'm not reproducing! The brightness and the color of the trails (information you'd be very good at making use of). But this is the 10-minutes-of-work result.
I'm sure there's software somewhere that can do this far better. I actually thought some such tool had been mentioned in the forum before, but I don't recall. I looked at a couple of tutorials on "reducing star trails in Photoshop", but they don't seem to apply to such lengthy trails.
Then, finally, I thought that
maybe you don't want this. Perhaps you were just wanting to see if you could handle the menrtal challenge without such tools, which would be considered cheating, in that case.
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 6:08 pm
by FLPhotoCatcher
Chris Peterson wrote: ↑Mon Sep 19, 2022 2:16 pm
FLPhotoCatcher wrote: ↑Mon Sep 19, 2022 6:23 am
Was this a single exposure, or is it a composite?
Almost certainly a stack of shorter images. Uncooled cameras cannot take such long exposures without dark current saturating their sensors.
That's what I was thinking. Also, it looks like a stacked image, but with some areas taken from a single exposure.
Per the photog's description on Instagram, "The photo shows six consecutive minutes of storm." I guess he took photos as close together as possible for six minutes, and stacked them somehow.
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Mon Sep 19, 2022 6:21 pm
by Ann
MarkBour wrote: ↑Mon Sep 19, 2022 5:14 pm
Ann wrote: ↑Mon Sep 19, 2022 4:44 am
I have to say that star trail pictures drive me slightly crazy. That is because I think I should be able to identify the stars, and I try, and I almost think I can do it
, but then I never can.
I get defeated every time.
Ann
Okay, I opened the image in Photoshop and made a new layer, putting a dot at the far left of each trail. When finished with that, I inserted a black mask in an intermediate layer. I immediately realized that there's lots of information I'm not reproducing! The brightness and the color of the trails (information you'd be very good at making use of). But this is the 10-minutes-of-work result.
I'm sure there's software somewhere that can do this far better. I actually thought some such tool had been mentioned in the forum before, but I don't recall. I looked at a couple of tutorials on "reducing star trails in Photoshop", but they don't seem to apply to such lengthy trails.
Then, finally, I thought that
maybe you don't want this. Perhaps you were just wanting to see if you could handle the menrtal challenge without such tools, which would be considered cheating, in that case.
Thanks, Mark, that's fantastic!
Unfortunately, I still don't recognize any star patterns.
You guessed that maybe I don't want to use the tools you used to "unscramble" star trail images. Unfortunately, you are correct. I want astronomy to be fun, and doing the kind of things you describe doesn't seem like fun to me.
Ann
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Tue Sep 20, 2022 6:23 am
by MarkBour
Ann wrote: ↑Mon Sep 19, 2022 6:21 pm
You guessed that maybe I don't want to use the tools you used to "unscramble" star trail images. Unfortunately, you are correct. I want astronomy to be fun, and doing the kind of things you describe doesn't seem like fun to me.
Ann
Okay, then how about this?
Go back to the original with only trails. I'm curious. Can you recognize any stars by the brightness and color of the trails?
I mean I certainly can't, but I wonder if that's possible for someone who knows what they're looking for.
If it is June in Barcelona, Spain, and if it is looking North, I think Vega and Deneb might be in view. One odd thing, though, the North star would be in the sky, but the shape of those star tracks make it seem that it would have been very high above this image, and that doesn't make sense.
Rauf wrote: ↑Mon Sep 19, 2022 5:37 am
The mountain is to the north and northwest of the Manlleu city. This picture was taken on June 9, after sunset. I tried recreating the scene in Stellarium and the only bright constellation that matched the star trails were stars of Cassiopeia. I am not sure how if fits though..
Ah. Nice. I went to Stellarium and repeated your steps, and sure enough, Cassiopeia is right in view. But it was only at about 15
o inclination, so I am wondering if it would have been right behind the storm cloud. Whatever is there, it should start with a "C". Near Cassiopeia, I see were Cepheus, Cygnus, and Camelopardalis. Even knowing that, though, I can't meet Ann's challenge from this photo.
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Tue Sep 20, 2022 8:10 am
by Rauf
MarkBour wrote: ↑Tue Sep 20, 2022 6:23 am
Ann wrote: ↑Mon Sep 19, 2022 6:21 pm
You guessed that maybe I don't want to use the tools you used to "unscramble" star trail images. Unfortunately, you are correct. I want astronomy to be fun, and doing the kind of things you describe doesn't seem like fun to me.
Ann
Okay, then how about this?
Go back to the original with only trails. I'm curious. Can you recognize any stars by the brightness and color of the trails?
I mean I certainly can't, but I wonder if that's possible for someone who knows what they're looking for.
If it is June in Barcelona, Spain, and if it is looking North, I think Vega and Deneb might be in view. One odd thing, though, the North star would be in the sky, but the shape of those star tracks make it seem that it would have been very high above this image, and that doesn't make sense.
Rauf wrote: ↑Mon Sep 19, 2022 5:37 am
The mountain is to the north and northwest of the Manlleu city. This picture was taken on June 9, after sunset. I tried recreating the scene in Stellarium and the only bright constellation that matched the star trails were stars of Cassiopeia. I am not sure how if fits though..
Ah. Nice. I went to Stellarium and repeated your steps, and sure enough, Cassiopeia is right in view. But it was only at about 15
o inclination, so I am wondering if it would have been right behind the storm cloud. Whatever is there, it should start with a "C". Near Cassiopeia, I see were Cepheus, Cygnus, and Camelopardalis. Even knowing that, though, I can't meet Ann's challenge from this photo.
I think because the mountain range is really far from the city, it doesn't cover that much of the sky. So it it should cover just around 5
o high. If you look at the star trails, if it was any higher than 15
o their trail's curve would have been greater, at least that is what I think.
I apologize for my bad English
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Tue Sep 20, 2022 8:13 am
by Rauf
Ann wrote: ↑Mon Sep 19, 2022 8:01 am
Rauf wrote: ↑Mon Sep 19, 2022 5:37 am
Ann wrote: ↑Mon Sep 19, 2022 4:44 am
That's a magnificent portrait of a ferocious storm and its torrent of lightning bolts.
That said, and this APOD being considered an image more suitable for an APOD than an
EPOD, I have to say that star trail pictures drive me slightly crazy. That is because I think I should be able to identify the stars, and I try, and I almost think I can do it
, but then I never can.
I get defeated every time.
It's like being shown a picture of a
galaxy and being told in the caption that this is a "galaxy", a generic specimen, and that is all you need to know. (Actually, the galaxy I gave you a link to is IC 342.)
Can anyone help me with today's APOD? Can someone out there identify any of the stars behind the star trails in this image?
Ann
The mountain is to the north and northwest of the Manlleu city. This picture was taken on June 9, after sunset. I tried recreating the scene in Stellarium and the only bright constellation that matched the star trails were stars of Cassiopeia. I am not sure how if fits though..
Thanks, Rauf! I was actually thinking of Cassiopeia myself. That long bright blue streak at top made me think of
Gamma Cas, but as for the rest of the constellation... I can't find it there.
Ann
Yeah, me too. I wish the photographer himself could explain! I always enjoy talking to them
Re: APOD: Star Trails and Lightning over the... (2022 Sep 19)
Posted: Wed Sep 21, 2022 5:48 am
by MarkBour
Rauf wrote: ↑Tue Sep 20, 2022 8:10 am
I think because the mountain range is really far from the city, it doesn't cover that much of the sky. So it it should cover just around 5
o high. If you look at the star trails, if it was any higher than 15
o their trail's curve would have been greater, at least that is what I think.
I apologize for my bad English
In that case, this makes sense. And your English is fine, too. Thanks.