Explanation: For a brief moment, this brilliant fireball meteor outshone Jupiter in planet Earth's night. The serendipitous image was captured while hunting meteors under cold Canadian skies with a camera in timelapse mode on December 14, near the peak of the Geminid meteor shower. The Geminid meteor shower, asteroid 3200 Phaethon's annual gift, always arrives in December. Dust shed along the orbit of the mysterious asteroid causes the meteor streaks, as the vaporizing grains plow through our fair planet's upper atmosphere at 22 kilometers per second. Of course Geminid shower meteors appear to radiate from a point in the constellation of the Twins. That's below and left of this frame. With bright Jupiter on the right, also in the December night skyview are the Pleiades and Hyades star clusters.
Hmmm,,, quick questions -
1) Brightest portion in the middle.. is that where the friction with Earth's atmosphere is the strongest (e.g. left origin up above atmosphere, so not that bright, right ending portion after the max burn falling down from sky) ? Or some other reason ?
2) Why blue-green light (i'd imagine it's based on composition/material of asteroid and if so, what's it made up of) ?
Thanks in advance to all answers/thoughts. I appreciate Ann and ChrisP, they respond most times to most people to most queries.
shaileshs wrote: ↑Thu Dec 28, 2023 5:20 am
Hmmm,,, quick questions -
1) Brightest portion in the middle.. is that where the friction with Earth's atmosphere is the strongest (e.g. left origin up above atmosphere, so not that bright, right ending portion after the max burn falling down from sky) ? Or some other reason ?
2) Why blue-green light (i'd imagine it's based on composition/material of asteroid and if so, what's it made up of) ?
Thanks in advance to all answers/thoughts. I appreciate Ann and ChrisP, they respond most times to most people to most queries.
I wish I knew, but meteors are not my forte at all. Chris should be able to provide you with good answers.
Nevertheless, I can say a few things. Take a look at this composite picture of Geminid meteors:
Note that the brightest meteor, at left, is clearly blue-green in color. But the fainter meteors are not green at all, certainly not blue-green. The fact that only the brighter meteors are blue-green certainly suggests to me that the size and mass of the meteor contributes to the green color, i.e., it takes a "powerful impact" between the meteor body and the Earth's atmosphere to create the green color. I think it has to do with the amount of energy created by meteor.
You can see the blue-green color of a bright meteor over Colorado:
Click to play embedded YouTube video.
However, not all bright meteors are green, although I do believe that many are. But the brightest meteor in recent years, the bolide over Chelyabinsk in Russia in 2013, does not appear to have been green at all. But if you watch the video below, you can hear loud "booms" as the meteor exploded.
Click to play embedded YouTube video.
I think that smaller meteors also "explode", at least sometimes. If you look at the first picture I posted, you can see two little brightenings in the trail of the brightest meteor. I would guess that those are little explosions as the pebble from space burnt up in the Earth's atmosphere.
It seems reasonable to me that the green color of many bright meteors might just possibly be related to the green color of comet comas:
The key player at the centre of the mystery, dicarbon, is both highly reactive and responsible for giving many comets their green colour. It’s made up of two carbon atoms stuck together and can only be found in extremely energetic or low oxygen environments like stars, comets and the interstellar medium.
Dicarbon doesn’t exist on comets until they get close to the Sun. As the Sun starts to warm the comet up, the organic matter living on the icy nucleus evaporates and moves to the coma. Sunlight then breaks up these larger organic molecules, creating dicarbon.
The UNSW-led team have now shown that as the comet gets even closer to the Sun, the extreme UV radiation breaks apart the dicarbon molecules it recently created in a process called ‘photodissociation’. This process destroys the dicarbon before it can move far from the nucleus, causing the green coma to get brighter and shrink – and making sure the green tinge never makes it into the tail.
Well, the process creating the green heads of comets doesn't seem to be the same as the process creating blue-green color in bright meteors. But the colors are similar. In any case, the color is caused by the matter and chemicals of the "meteor body" reacting to the rapidly increasing heat and pressure as it falls through the Earth's atmosphere. But you knew that already.
As for why the meteor is brightest in the middle, well, consider the Chelyabinsk meteor: First it was faint, then it got bright, then it got faint again. And actually, I think we can see signs of little explosions in the middle of the trail of the bright meteor of the APOD.
shaileshs wrote: ↑Thu Dec 28, 2023 5:20 am
Hmmm,,, quick questions -
1) Brightest portion in the middle.. is that where the friction with Earth's atmosphere is the strongest (e.g. left origin up above atmosphere, so not that bright, right ending portion after the max burn falling down from sky) ? Or some other reason ?
2) Why blue-green light (i'd imagine it's based on composition/material of asteroid and if so, what's it made up of) ?
Thanks in advance to all answers/thoughts. I appreciate Ann and ChrisP, they respond most times to most people to most queries.
The meteor trail is probably a few centimeters wide. In other words, at this scale it's an unresolved line with zero width. So the apparent width of the line is determined by brightness and optics (diffraction and scatter), just like the apparent sizes of stars are in images.
Meteor color is complex, determined by the meteoroid material, by the atmospheric gases and gas densities it is passing through, and by the nature of either the camera filters and processing, or our eye/brain processing. Elements like iron and magnesium can emit in the blue/green region, but so can oxygen in the atmosphere. And I'll note that the color processing of this image isn't the best, with virtually no star color showing, and what little there is seems to have a slight green cast. So I wouldn't try to overanalyze the apparent color too deeply. To really get an idea of meteoroid composition we need to look at the trail spectroscopically. Three broadband filters centered on red, green, and blue lose too much information.
Chris
*****************************************
Chris L Peterson
Cloudbait Observatory https://www.cloudbait.com
So why is asteroid Phaethon described here as "mysterious"? Not sure, but from Wikipedia it could be a few things (though I'd say it makes Phaethon unusual and interesting rather than mysterious):
https://en.wikipedia.org/wiki/3200_Phaethon wrote:
Its most remarkable distinction is that it approaches the Sun closer than any other named asteroid: its perihelion is only 0.14 AU (20.9 million km; 13.0 million mi) — less than half of Mercury's perihelial distance.
...
Phaethon is categorized as a potentially hazardous asteroid (PHA),[1][14] but that does not mean there is a near-term threat of an impact. It is a potentially hazardous asteroid merely as a result of its size (absolute magnitude H ≤ 22) and Earth minimum orbit intersection distance (Earth MOID ≤ 0.05 AU).
...
Phaethon is an asteroid with fairly unusual characteristics in that its orbit more closely resembles that of a comet than an asteroid; it has been referred to as a "rock comet".[16] In studies performed by NASA's STEREO spacecraft in 2009 and 2012, rapid brightening and dust tail have been observed.[17][18][19] It is possible that the Sun's heat is causing fractures similar to mud cracks in a dry lake bed.[20]
...
In 2018, observations revealed that Phaethon was blue in color. This is extremely rare, as most asteroids tend to be grey or red.[21][22] In 2020, polarimetric study revealed Phaethon has a surface with steep slopes covered by a mix of regolith with larger pebbles.[23]
-- "To B̬̻̋̚o̞̮̚̚l̘̲̀᷾d̫͓᷅ͩḷ̯᷁ͮȳ͙᷊͠ Go......Beyond The F͇̤i̙̖e̤̟l̡͓d͈̹s̙͚ We Know."{ʲₒʰₙNYᵈₑᵉₚ}
shaileshs wrote: ↑Thu Dec 28, 2023 5:20 am
Hmmm,,, quick questions -
1) Brightest portion in the middle.. is that where the friction with Earth's atmosphere is the strongest (e.g. left origin up above atmosphere, so not that bright, right ending portion after the max burn falling down from sky) ? Or some other reason ?
2) Why blue-green light (i'd imagine it's based on composition/material of asteroid and if so, what's it made up of) ?
Thanks in advance to all answers/thoughts. I appreciate Ann and ChrisP, they respond most times to most people to most queries.
About the blue-green color. It's apparent to me that the photo has been enhanced to greatly increase the blue-green color. See how the blue-green color extends out perpendicular from the meteor trail, widest in the middle... The color extends into the black of the sky, then stops at a sharp edge. That does not happen without some fiddling with the photo.
It's still a great photo, but I wish it was not modified so much.
shaileshs wrote: ↑Thu Dec 28, 2023 5:20 am
Hmmm,,, quick questions -
1) Brightest portion in the middle.. is that where the friction with Earth's atmosphere is the strongest (e.g. left origin up above atmosphere, so not that bright, right ending portion after the max burn falling down from sky) ? Or some other reason ?
2) Why blue-green light (i'd imagine it's based on composition/material of asteroid and if so, what's it made up of) ?
Thanks in advance to all answers/thoughts. I appreciate Ann and ChrisP, they respond most times to most people to most queries.
About the blue-green color. It's apparent to me that the photo has been enhanced to greatly increase the blue-green color. See how the blue-green color extends out perpendicular from the meteor trail, widest in the middle... The color extends into the black of the sky, then stops at a sharp edge. That does not happen without some fiddling with the photo.
It's still a great photo, but I wish it was not modified so much.
I agree. The color of the meteor is quite unrealistic (as Chris also pointed out). Also, like Chris, I found it very strange that the background stars are virtually all colorless.
Let's compare the APOD with two pictures of Geminid meteors against a starry background:
A young friend of mine saw a very bright bolide over my hometown of Malmö some ten years ago. (I was so envious of him for having seen it!) The bolide was bright enough that it made national news. But when my friend described it, this is what he said about it:
"It was green!"
So, yes. I believe that bright meteors are often green. But they are typically blue-green, not a "pure" shade of green, and their color is not saturated. In other words, they are perhaps this color, ███, not this color, ███.
I agree. The color of the meteor is quite unrealistic (as Chris also pointed out). Also, like Chris, I found it very strange that the background stars are virtually all colorless.
Let's compare the APOD with two pictures of Geminid meteors against a starry background:
A young friend of mine saw a very bright bolide over my hometown of Malmö some ten years ago. (I was so envious of him for having seen it!) The bolide was bright enough that it made national news. But when my friend described it, this is what he said about it:
"It was green!"
So, yes. I believe that bright meteors are often green. But they are typically blue-green, not a "pure" shade of green, and their color is not saturated. In other words, they are perhaps this color, ███, not this color, ███.
Ann
The last photo is colorful but I can't see or distinguish clearly what color it is. But I have to admit it's really excellent.
Last edited by bystander on Tue Mar 12, 2024 2:10 pm, edited 1 time in total.
Reason:removed tynde spam
This shoot si about last Geminid meteor shower in Dolomites
Intro: This shoot is dedicated to my beloved dog passed away at the end of November.
The 14th of December there was the peak of Geminid meteor shower, so i decided to plan this special shoot for her in Dolomites where we had done a lot of trekking together in those years.
Blend/Stacked
Geminids, and the Quadrantids, are the major meteor showers not originating from a comet.
Maybe you don't know that Geminids swarm is becoming extinct. Over the course of about a century, scientists have predicted that the swarm will be completely exhausted, due to the fact that with each passage, fragments of 3200 Phaetons are disintegrated in greater and greater numbers in the Earth's atmosphere.
Meteors have also different kinds of colours it's depend on their chemical composition,different chemicals in the meteors give different colors as they burn up while entering the Earth’s atmosphere.
For example, meteors made from primarily calcium will give off a purple or violet color, while those made out of magnesium will appear to have a green or teal color, blue color for iron composition, orange for sodium and red color for oxygen.
The speed at which the meteor enters the Earth’s atmosphere can also affect the color, slow meteors are red or orange and fast meteors frequently have a blue color.
Fujifilm X-T3
Land 1x30" f/5.6 iso 160 Nisi 9mm 2.8
Sky 8x8" f/2 iso 3200 Sigma 30mm 1.4
Meteors (I choose the brightest) 900x8" f/2 iso 3200 Sigma 30mm 1.4
Last edited by Nicolò Taborra on Mon Jan 08, 2024 6:54 pm, edited 7 times in total.
This shoot si about last Geminid meteor shower in Dolomites
Intro: This shoot is dedicated to my beloved dog passed away at the end of November.
The 14th of December there was the peak of Geminid meteor shower, so i decided to plan this special shoot for her in Dolomites where we had done a lot of trekking together in those years.
Blend/Stacked
Geminids, and the Quadrantids, are the major meteor showers not originating from a comet.
Maybe you don't know that Geminids swarm is becoming extinct. Over the course of about a century, scientists have predicted that the swarm will be completely exhausted, due to the fact that with each passage, fragments of 3200 Phaetons are disintegrated in greater and greater numbers in the Earth's atmosphere.
Meteors have also different kinds of colours it's depend on their chemical composition,different chemicals in the meteors give different colors as they burn up while entering the Earth’s atmosphere.
For example, meteors made from primarily calcium will give off a purple or violet color, while those made out of magnesium will appear to have a green or teal color, blue color for iron composition, orange for sodium and red color for oxygen.
The speed at which the meteor enters the Earth’s atmosphere can also affect the color, slow meteors are red or orange and fast meteors frequently have a blue color.
Fujifilm X-T3
Land 1x30" f/5.6 iso 160 Nisi 9mm 2.8
Sky 8x8" f/2 iso 3200 Sigma 30mm 1.4
Meteors (I choose the brightest) 900x8" f/2 iso 3200 Sigma 30mm 1.4
Note: you can't use a facebook link with the url tags. You'll see that it appears "broken" in your post. But you can use a direct link to the facebook image, like so - nice image by the way! :
This shoot si about last Geminid meteor shower in Dolomites
Intro: This shoot is dedicated to my beloved dog passed away at the end of November.
The 14th of December there was the peak of Geminid meteor shower, so i decided to plan this special shoot for her in Dolomites where we had done a lot of trekking together in those years.
Blend/Stacked
Geminids, and the Quadrantids, are the major meteor showers not originating from a comet.
Maybe you don't know that Geminids swarm is becoming extinct. Over the course of about a century, scientists have predicted that the swarm will be completely exhausted, due to the fact that with each passage, fragments of 3200 Phaetons are disintegrated in greater and greater numbers in the Earth's atmosphere.
Meteors have also different kinds of colours it's depend on their chemical composition,different chemicals in the meteors give different colors as they burn up while entering the Earth’s atmosphere.
For example, meteors made from primarily calcium will give off a purple or violet color, while those made out of magnesium will appear to have a green or teal color, blue color for iron composition, orange for sodium and red color for oxygen.
The speed at which the meteor enters the Earth’s atmosphere can also affect the color, slow meteors are red or orange and fast meteors frequently have a blue color.
Fujifilm X-T3
Land 1x30" f/5.6 iso 160 Nisi 9mm 2.8
Sky 8x8" f/2 iso 3200 Sigma 30mm 1.4
Meteors (I choose the brightest) 900x8" f/2 iso 3200 Sigma 30mm 1.4
Note: you can't use a facebook link with the url tags. You'll see that it appears "broken" in your post. But you can use a direct link to the facebook image, like so - nice image by the way! :
Hi there! I'm new here, just landed on Asterisk
...
Hi thanks for your comment, but i'm not very able to use this forum i try to correct removing the url tags and paste only the FB link, it's ok now ?
Yes, your original post now shows a working facebook link, but not the picture itself. But, you can also get the url for the image itself (my browser has a right-click/copy image address option) and post that direct link using the img tags. This is the direct link I used above:
Yes, your original post now shows a working facebook link, but not the picture itself. But, you can also get the url for the image itself (my browser has a right-click/copy image address option) and post that direct link using the img tags. This is the direct link I used above:
Yes, your original post now shows a working facebook link, but not the picture itself. But, you can also get the url for the image itself (my browser has a right-click/copy image address option) and post that direct link using the img tags. This is the direct link I used above:
Jupiter and the Geminid
i try to correct removing the url tags and paste only the FB link, it's ok now ?
