Comments and questions about the
APOD on the main view screen.
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daddyo
- Science Officer
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by daddyo » Wed Aug 09, 2023 6:17 am
Really nice composite.
Is anyone familiar with software or script that’s good for detecting meteors in a captured video?
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randomuser
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by randomuser » Wed Aug 09, 2023 9:19 am
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Bartolo
- Asternaut
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by Bartolo » Wed Aug 09, 2023 6:18 pm
The meteor shower seems to radiate from a central point, but actually radiates towards a central point: Earth's.
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johnnydeep
- Commodore
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by johnnydeep » Wed Aug 09, 2023 6:42 pm
Bartolo wrote: ↑Wed Aug 09, 2023 6:18 pm
The meteor shower seems to radiate from a central point, but actually radiates
towards a central point: Earth's.
What do you mean by that? The Earth's gravity attracts the cometary debris particles when they get close enough, but the debris itself is in orbit around the Sun.
--
"To B̬̻̋̚o̞̮̚̚l̘̲̀᷾d̫͓᷅ͩḷ̯᷁ͮȳ͙᷊͠ Go......Beyond The F͇̤i̙̖e̤̟l̡͓d͈̹s̙͚ We Know."{ʲₒʰₙNYᵈₑᵉₚ}
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orin stepanek
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by orin stepanek » Wed Aug 09, 2023 8:08 pm
There's a lot of junk in orbit from these comets that come and visit
the solar system! I'm just glad that they are very small!
Orin
Smile today; tomorrow's another day!
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Bartolo
- Asternaut
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by Bartolo » Wed Aug 09, 2023 11:44 pm
johnnydeep wrote: ↑Wed Aug 09, 2023 6:42 pm
What do you mean by that? The Earth's gravity attracts the cometary debris particles when they get close enough, but the debris itself is in orbit around the Sun.
I'm only talking about the debris entering the atmosphere. Do the trajectories tend to be parallel to each other, or perpendicular to Earth's surface? Slight difference.
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Chris Peterson
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Contact:
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by Chris Peterson » Thu Aug 10, 2023 4:06 am
Bartolo wrote: ↑Wed Aug 09, 2023 11:44 pm
johnnydeep wrote: ↑Wed Aug 09, 2023 6:42 pm
What do you mean by that? The Earth's gravity attracts the cometary debris particles when they get close enough, but the debris itself is in orbit around the Sun.
I'm only talking about the debris entering the atmosphere. Do the trajectories tend to be parallel to each other, or perpendicular to Earth's surface? Slight difference.
The trajectories in the atmosphere are largely parallel to each other. There is some effect of Earth's gravity on the body, bending it slightly toward the Earth, which shifts the apparent radiant slightly (called zenith attraction). It's something we correct for when working backwards from meteor trails to parent body orbits. But the substantial component of the meteor path lies fairly close to its original path. So to a first order and reasonable approximation, we can consider all the meteors to be in parallel paths until they burn up. Their angle with respect to the surface depends on where they intersect the atmosphere- perpendicular for meteors centered on the planet, parallel for grazing meteors.
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Ann
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by Ann » Thu Aug 10, 2023 4:21 am
I very much appreciate the learned discussions between Johnny and Chris, but I have nothing to add there, so let me add the pretty pictures!
Like I said, pretty!
Does anyone know what that bright orange light near bottom left could be? Is it by any chance Mars?
Ann
Color Commentator
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daddyo
- Science Officer
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by daddyo » Thu Aug 10, 2023 5:21 am
Thanks!! Going to try it on this weekend’s shower.
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Rauf
- Science Officer
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by Rauf » Thu Aug 10, 2023 9:11 am
Ann wrote: ↑Thu Aug 10, 2023 4:21 am
I very much appreciate the learned discussions between Johnny and Chris, but I have nothing to add there, so let me add the pretty pictures!
APOD 9 August 2023 annotated.png
Like I said, pretty!
Does anyone know what that bright orange light near bottom left could be? Is it by any chance Mars?
Ann
Using Stellarium again, I went to Slovakia in August 2018.
So yes, It is Mars!
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johnnydeep
- Commodore
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by johnnydeep » Thu Aug 10, 2023 2:02 pm
Ann wrote: ↑Thu Aug 10, 2023 4:21 am
I very much appreciate the learned discussions between Johnny and Chris, but I have nothing to add there, so let me add the pretty pictures!
...
Ann
Well, Chris' contribution was indeed learned, but mine was merely to add more context to further the dialog.
--
"To B̬̻̋̚o̞̮̚̚l̘̲̀᷾d̫͓᷅ͩḷ̯᷁ͮȳ͙᷊͠ Go......Beyond The F͇̤i̙̖e̤̟l̡͓d͈̹s̙͚ We Know."{ʲₒʰₙNYᵈₑᵉₚ}