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APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 4:05 am
by APOD Robot
Image Meteor before Galaxy

Explanation: What's that green streak in front of the Andromeda galaxy? A meteor. While photographing the Andromeda galaxy last Friday, near the peak of the Perseid Meteor Shower, a sand-sized rock from deep space crossed right in front of our Milky Way Galaxy's far-distant companion. The small meteor took only a fraction of a second to pass through this 10-degree field. The meteor flared several times while braking violently upon entering Earth's atmosphere. The green color was created, at least in part, by the meteor's gas glowing as it vaporized. Although the exposure was timed to catch a Perseids meteor, the orientation of the imaged streak seems a better match to a meteor from the Southern Delta Aquariids, a meteor shower that peaked a few weeks earlier.

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Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 4:39 am
by daddyo
I think it's space lightning

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 5:11 am
by alter-ego
APOD Robot wrote:... the orientation of the imaged streak seems a better match to a meteor from the Southern Delta Aquariids, a meteor shower that peaked a few weeks earlier.
Ignoring travel direction, the track alignment is right on the money with Kappa Cygnids which although peaks on ~8/17, actually is active from 8/3 to 8/25. Granted a listed ZHR of ~3 is very low but the track alignment with the radiant is too good to ignore and it misses the Delta Aquariids radiant significantly. I believe a meteor path is a great circle on the celestial sphere, in which case a DA meteor would run almost parallel the M31 (~110° off from the imaged meteor). However, it looks like the meteor may have traveled from top to bottom bottom to top which makes both radiants questionable.

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 5:34 am
by Ann
The color of the meteor is very green and unchanging. My impression is that most meteor images show the meteors to be generally changing color, and while they may well be green, this sharply yellow-green and unchanging color is one I have not seen in photos before.

Ann

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 6:07 am
by astrometbcn
Hi

The Sony A7s rgb and SX -36 camera monochrome, two at a time? or the meteor was captured by the SX -36 monochrome and then he has painted the green colour??

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 10:21 am
by hamilton1
omg what a brilliant image.

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 11:01 am
by astrometbcn
I do not understand from where the color, if only captured the meteor with monochrome ccd, for now remains only clarify whether he caught the meteor with ccd or if it could also capture also with the dslr rgb.......

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 12:57 pm
by Hunter
astrometbcn wrote:I do not understand from where the color, if only captured the meteor with monochrome ccd, for now remains only clarify whether he caught the meteor with ccd or if it could also capture also with the dslr rgb.......
You need to learn more before commenting

As he said in his flickr:

Technique: parallel exposure with two imaging systems:
(1) Canon 200mm/F1.8 (open), SX-36, L-pro filter, 240 sec exposure time,
(2) Canon 200mm/F1.8 (open), Sony A7s (CentralDS modded), ISO 3200, IDAS-V4 filter, 90 sec
both on EQ8 mount unguided.
Final image processed with 32 subframes from each system for the galaxy and the stars resulting in a L-RGB image.
Tenerife, 1180 m alt, 2016-08-12 00:45 UT

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 1:57 pm
by Astronymus
Could the nearly equal flare burst be caused by rotation of the object?

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 2:08 pm
by caliu
Hunter wrote:
astrometbcn wrote:I do not understand from where the color, if only captured the meteor with monochrome ccd, for now remains only clarify whether he caught the meteor with ccd or if it could also capture also with the dslr rgb.......
You need to learn more before commenting

As he said in his flickr:

Technique: parallel exposure with two imaging systems:
(1) Canon 200mm/F1.8 (open), SX-36, L-pro filter, 240 sec exposure time,
(2) Canon 200mm/F1.8 (open), Sony A7s (CentralDS modded), ISO 3200, IDAS-V4 filter, 90 sec
both on EQ8 mount unguided.
Final image processed with 32 subframes from each system for the galaxy and the stars resulting in a L-RGB image.
Tenerife, 1180 m alt, 2016-08-12 00:45 UT
Mr Hunter,
Why should we believe?

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 2:30 pm
by Jim-1920
The link for the larger image has a filetype of "gif." Should be "jpg."

http://apod.nasa.gov/apod/image/1608/Me ... h_1948.gif <----

Jim

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 2:55 pm
by Hunter
Dear astrometbcn,

Why you write in Spanish if I wrote in English, with these moderate ways?

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 3:09 pm
by Fred the Cat
Serendipity :ssmile:

Great catch but was the show(er) as good as expected :?:

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 4:26 pm
by Bellerophon
It's an astronomical photobomb!

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 4:36 pm
by loquin
The color of the meteor is very green and unchanging. My impression is that most meteor images show the meteors to be generally changing color, and while they may well be green, this sharply yellow-green and unchanging color is one I have not seen in photos before.

Ann
Ann, while it may be rare to photograph them, they do happen... One I saw some time ago flared in green as it appeared, then the trail looked like an unchanging brilliant green bar until it died. The other thing to remember here, is that with the photo shown, the path of the meteor only covers about 5-6 degrees of the sky top-to-bottom, so we're probably only seeing a portion, possibly a small portion, of the entire meteor track. That being the case, the chances of seeing a color change in the reduced portion of the total track is also reduced.

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 4:40 pm
by No hunter
:P

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 4:45 pm
by No hunter
That sounds like a witch on her broomstick :lol2: :lol2:

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 5:23 pm
by Ann
loquin wrote:
The color of the meteor is very green and unchanging. My impression is that most meteor images show the meteors to be generally changing color, and while they may well be green, this sharply yellow-green and unchanging color is one I have not seen in photos before.

Ann
Ann, while it may be rare to photograph them, they do happen... One I saw some time ago flared in green as it appeared, then the trail looked like an unchanging brilliant green bar until it died. The other thing to remember here, is that with the photo shown, the path of the meteor only covers about 5-6 degrees of the sky top-to-bottom, so we're probably only seeing a portion, possibly a small portion, of the entire meteor track. That being the case, the chances of seeing a color change in the reduced portion of the total track is also reduced.
That's true. We only saw the meteor cross Andromeda, and Andromeda isn't that large in the sky (although it isn't that small either).

Ann

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 6:45 pm
by Boomer12k
"...and they called him, "the streeeeaakk.."

Song from the 70's, I think...

Really great shot...

:---[===] *

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 7:23 pm
by BMAONE23
Andromeda should consider herself fortunate, If the track had been even slightly different (viewpoint anyway) Her heart would have been pierced

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Wed Aug 17, 2016 7:38 pm
by Maksu70
It seems to me very unlikely a meteor path so much perpendicular to M31, so near the center and with the blast happenning symetrically at both sides of M31

Can this photo be a composition?

If the meteor happens at 100km of height, does this means that if the photographer had chossen a place 2 km away he would had missed the photo?
(100km*tan(1 degree)=1,7 km
Does the radiant concept for a meteor shower imply the above calculation is wrong?

Can be calculated the probability that for a person that is photographying M31, a so centered, perpendicular ans symetric meteor passes over M31?, then multiplying this probability by the number of photographers on earth we can calculate how fortunately we have been or if we can be skeptical about this is not a composition

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Thu Aug 18, 2016 3:07 am
by Chris Peterson
Ann wrote:The color of the meteor is very green and unchanging. My impression is that most meteor images show the meteors to be generally changing color, and while they may well be green, this sharply yellow-green and unchanging color is one I have not seen in photos before.
One reason that images show changing color has to do with individual color channels on the sensor being saturated at different points along the path. Another thing to consider is that green in meteors typically is the result of atmospheric oxygen. Shallow meteor paths and meteors that burn up quickly have everything happening in a similar atmospheric regime, and are more likely to show the same color. Those that descend steeply pass through different atmosphere which can result in different colors. Some meteors that show different colors do so because we're also seeing spectral contributions from the meteoroid itself (especially with sporadic, asteroidal material), and different elements burn off at different times, depending on temperature.

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Thu Aug 18, 2016 9:45 am
by geckzilla
To all Spanish-speaking friends: Please post in English if you can. It was ok for a few posts in the Mars thread, but I can't read Spanish and I have a very hard time understanding the tone of a post since I know so little of it. Auto translate is not good enough many times and confusion can easily lead to misunderstanding and negative interactions on the forum.

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Thu Aug 18, 2016 5:30 pm
by Спасибо
geckzilla wrote:To all Spanish-speaking friends: Please post in English if you can. It was ok for a few posts in the Mars thread, but I can't read Spanish and I have a very hard time understanding the tone of a post since I know so little of it. Auto translate is not good enough many times and confusion can easily lead to misunderstanding and negative interactions on the forum.

Да , с английского на русский язык является достаточно сложным делом , не бросать испанский в на вершине этого .

Re: APOD: Meteor before Galaxy (2016 Aug 17)

Posted: Thu Aug 18, 2016 6:14 pm
by Astronymus
Спасибо wrote:
geckzilla wrote:To all Spanish-speaking friends: Please post in English if you can. It was ok for a few posts in the Mars thread, but I can't read Spanish and I have a very hard time understanding the tone of a post since I know so little of it. Auto translate is not good enough many times and confusion can easily lead to misunderstanding and negative interactions on the forum.

Да , с английского на русский язык является достаточно сложным делом , не бросать испанский в на вершине этого .
Volltreffer. Nicht jeder spricht zwanzig oder mehr Fremdsprachen. In einem englischsprachigen Forum sollte man auch bei Englisch bleiben.