Comments and questions about the
APOD on the main view screen.
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APOD Robot
- Otto Posterman
- Posts: 5601
- Joined: Fri Dec 04, 2009 3:27 am
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by APOD Robot » Sat Sep 12, 2020 4:07 am
A Thousand Meteors
Explanation: Over a thousand meteors flash through the night in this
intriguing timelapse video. Starting in April 2019 the individual video frames were selected from 372 relatively clear nights of imaging from an automated wide-field observatory in rural New South Wales Australia. Arranged by
local sidereal time, a timekeeping system that uses the positions of stars to measure Earth's rotation, the frames follow the full annual progression of constellations through the wide field of view seen from 33 degrees south latitude. They capture a
diverse array of meteors including
sporadic meteors, bright fireballs, and shower meteors (plus a
lightning sprite), during the period. All frames were processed consistently and so show real variations in the local sky conditions.
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heehaw
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by heehaw » Sat Sep 12, 2020 11:46 am
Fabulous! Wonderful! Super indeed!
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orin stepanek
- Plutopian
- Posts: 8200
- Joined: Wed Jul 27, 2005 3:41 pm
- Location: Nebraska
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by orin stepanek » Sat Sep 12, 2020 12:02 pm
I had to look twice, I thought the subject was meters at first!
Oh; there's an O in there!
Orin
Smile today; tomorrow's another day!
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sillyworm 2
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by sillyworm 2 » Sat Sep 12, 2020 12:52 pm
Saw one the other night..just happened to be looking at the sky.Slightly more special than when you're looking on a night of a shower.
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De58te
- Commander
- Posts: 584
- Joined: Mon Sep 30, 2013 6:35 pm
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by De58te » Sat Sep 12, 2020 1:01 pm
So in spite of the headline the video was intended to show sidereal time of the Earth's rotation? Nevertheless a thousand meteors seen over 372 nights works out to less than 3 meteors a night! That's about right since that's the most meteors I wind up seeing a night during a meteor shower.
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johnnydeep
- Commodore
- Posts: 3248
- Joined: Sun Feb 20, 2011 8:57 pm
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by johnnydeep » Sat Sep 12, 2020 3:47 pm
APOD Robot wrote: ↑Sat Sep 12, 2020 4:07 am
A Thousand Meteors
Explanation: Over a thousand meteors flash through the night in this
intriguing timelapse video. Starting in April 2019 the individual video frames were selected from 372 relatively clear nights of imaging from an automated wide-field observatory in rural New South Wales Australia. Arranged by
local sidereal time, a timekeeping system that uses the positions of stars to measure Earth's rotation, the frames follow the full annual progression of constellations through the wide field of view seen from 33 degrees south latitude. They capture a
diverse array of meteors including
sporadic meteors, bright fireballs, and shower meteors (plus a
lightning sprite), during the period. All frames were processed consistently and so show real variations in the local sky conditions.
Ok, so it took me a little while to appreciate that "Arranged by local sidereal time" means that the 372 separate night pictures, which were all taken at different times of the day, were reshuffled to appear in local sidereal time order so that we get the illusion of a single day progressing through a rotating starry sky, correct?
Also at 0:52 in the video, what are these two things - I want to say the little one is the SMC, but then the bigger one should be the LMC, but it looks too diffuse:
What Are These.JPG
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"To B̬̻̋̚o̞̮̚̚l̘̲̀᷾d̫͓᷅ͩḷ̯᷁ͮȳ͙᷊͠ Go......Beyond The F͇̤i̙̖e̤̟l̡͓d͈̹s̙͚ We Know."{ʲₒʰₙNYᵈₑᵉₚ}
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Chris Peterson
- Abominable Snowman
- Posts: 18611
- Joined: Wed Jan 31, 2007 11:13 pm
- Location: Guffey, Colorado, USA
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by Chris Peterson » Sat Sep 12, 2020 4:08 pm
De58te wrote: ↑Sat Sep 12, 2020 1:01 pm
So in spite of the headline the video was intended to show sidereal time of the Earth's rotation? Nevertheless a thousand meteors seen over 372 nights works out to less than 3 meteors a night! That's about right since that's the most meteors I wind up seeing a night during a meteor shower.
The camera probably captures a dozen or more meteors on most nights, and hundreds per night during showers. That's what I see with mine.
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alter-ego
- Serendipitous Sleuthhound
- Posts: 1123
- Joined: Mon Apr 21, 2008 4:51 am
- Location: Redmond, WA
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by alter-ego » Sat Sep 12, 2020 4:13 pm
johnnydeep wrote: ↑Sat Sep 12, 2020 3:47 pm
...
Also at 0:52 in the video, what are these two things - I want to say the little one is the SMC, but then the bigger one should be the LMC, but it looks too diffuse:
What Are These.JPG
The arrow points to the Pleiades, and you've circle contains Orions belt and sword w/ M42.
Remember, constellations are upside down down under. I had a ball identifying familiar constellations when I was in Australia for Halley.
A pessimist is nothing more than an experienced optimist
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johnnydeep
- Commodore
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Post
by johnnydeep » Sat Sep 12, 2020 4:41 pm
alter-ego wrote: ↑Sat Sep 12, 2020 4:13 pm
johnnydeep wrote: ↑Sat Sep 12, 2020 3:47 pm
...
Also at 0:52 in the video, what are these two things - I want to say the little one is the SMC, but then the bigger one should be the LMC, but it looks too diffuse:
What Are These.JPG
The arrow points to the Pleiades, and you've circle contains Orions belt and sword w/ M42.
Remember, constellations are upside down down under. I had a ball identifying familiar constellations when I was in Australia for Halley.
Ok, thanks. That makes sense.
--
"To B̬̻̋̚o̞̮̚̚l̘̲̀᷾d̫͓᷅ͩḷ̯᷁ͮȳ͙᷊͠ Go......Beyond The F͇̤i̙̖e̤̟l̡͓d͈̹s̙͚ We Know."{ʲₒʰₙNYᵈₑᵉₚ}
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gvann
- Ensign
- Posts: 11
- Joined: Tue Oct 15, 2019 1:00 am
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by gvann » Sat Sep 12, 2020 4:50 pm
I wonder what trees those are. Their foliage seems not to change at all during the year (although the tree in the upper right lost a small branch at some point). So, they must be some kind of evergreens. But they don't look to me like anything that I am familiar with in the northeastern USA.
GV
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goatrider
- Asternaut
- Posts: 2
- Joined: Sat Nov 23, 2013 3:50 pm
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by goatrider » Sat Sep 12, 2020 5:07 pm
orin stepanek wrote: ↑Sat Sep 12, 2020 12:02 pm
I had to look twice, I thought the subject was meters at first!
Oh; there's an O in there!
So it's a "Kilometeor".
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Sa Ji Tario
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by Sa Ji Tario » Sat Sep 12, 2020 7:08 pm
It is not the USA, it is Australia and you can also see Aldebaran, in the head of Taurus and the Hiades
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heehaw
Post
by heehaw » Sat Sep 12, 2020 8:11 pm
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alter-ego
- Serendipitous Sleuthhound
- Posts: 1123
- Joined: Mon Apr 21, 2008 4:51 am
- Location: Redmond, WA
Post
by alter-ego » Sun Sep 13, 2020 1:42 am
gvann wrote: ↑Sat Sep 12, 2020 4:50 pm
I wonder what trees those are. Their foliage seems not to change at all during the year (although the tree in the upper right lost a small branch at some point). So, they must be some kind of evergreens. But they don't look to me like anything that I am familiar with in the northeastern USA.
GV
Most likely the tree is an evergreen species of
Eucalyptus. I recall seeing them all over when I was in Victoria.
A pessimist is nothing more than an experienced optimist
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Greg_Priestley
- Asternaut
- Posts: 4
- Joined: Wed Nov 14, 2012 7:16 am
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by Greg_Priestley » Tue Oct 06, 2020 9:20 pm
De58te wrote: ↑Sat Sep 12, 2020 1:01 pm
So in spite of the headline the video was intended to show sidereal time of the Earth's rotation? Nevertheless a thousand meteors seen over 372 nights works out to less than 3 meteors a night! That's about right since that's the most meteors I wind up seeing a night during a meteor shower.
There is more nuance. I actually identified 2,686 meteor frames from 570,518 discrete images shot across the 372 nights. I then down selected these -a lot of frames had the moon or were moon lit, and this caused even more excessive jarring brightness changes frame to frame. Others whilst they could be identified weren't significant enough to be recognisable during playback. Finally, some were dropped because there were also satellite trails in the frame, frequently more obvious, so didn't want to confuse the issue.
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Greg_Priestley
- Asternaut
- Posts: 4
- Joined: Wed Nov 14, 2012 7:16 am
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by Greg_Priestley » Tue Oct 06, 2020 9:21 pm
goatrider wrote: ↑Sat Sep 12, 2020 5:07 pm
orin stepanek wrote: ↑Sat Sep 12, 2020 12:02 pm
I had to look twice, I thought the subject was meters at first!
Oh; there's an O in there!
So it's a "Kilometeor".
I might have to steal that.
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Greg_Priestley
- Asternaut
- Posts: 4
- Joined: Wed Nov 14, 2012 7:16 am
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by Greg_Priestley » Tue Oct 06, 2020 9:29 pm
johnnydeep wrote: ↑Sat Sep 12, 2020 3:47 pm
Ok, so it took me a little while to appreciate that "Arranged by local sidereal time" means that the 372 separate night pictures, which were all taken at different times of the day, were reshuffled to appear in local sidereal time order so that we get the illusion of a single day progressing through a rotating starry sky, correct?
Correct - if I play them back per capture time, it's very dizzying to watch as the sky jumps from frame to frame can be very dramatic - and it makes it hard to pick out the meteors with all the other movement also occurring frame to frame.
My original objective for the project was to do in effect a continuous seamless 360 degree of the full constellations that are seen, but the footage from December thru February were significantly affected by the bushfires that we had here last year which killed that plan.
Other variations from the project can be seen at:
https://www.astroimaging.gallery/