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A Twisted Meteor Trail Over Tenerife

Explanation: Did this meteor take a twisting path? No one is sure. Considered opinions are solicited. Meteors, usually sand sized grains that originate in comets, will typically disintegrate as they enter the Earth's atmosphere. A fast moving meteor ionizes molecules in the Earth's atmosphere that subsequently glow when they reacquire electrons. Meteor paths that twist noticeably have been noted before, and even photographed, but attributing such behavior to the motion of the meteor itself and neither the wind-blown meteor train nor the observer remains somewhat controversial. The above meteor, imaged two weeks ago streaking over the Teide Observatory in Tenerife, Canary Islands, appears to swagger as much as several minutes of arc, which the experienced astrophotographer did not think could be attributed to drifting of the resulting train or motion of the camera mount. If truly an indication of a twisted meteor path, an underlying reason could be the pictured meteor was markedly non-spherical in shape, non-uniform in composition, or electrically charged. Non-uniform meteors, for example, may evaporate more on one side than another, causing a rotating meteor to wobble. Understanding meteors is important partly because meteors are candidates to have seeded Earth with prebiotic molecules that allowed for the development of life.

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Knuckleball meteor!

I vote for an unsymmetrical meteor (either geometrically, or in its composition, or both) that acquires a spin as it passes through the atmosphere and then emits a jet of gas from one side as it heats up. I believe that would cause the observed helical path.

If it was a knuckle ball, it would have a BIG curve to it. It most likely just passed through a bit of turbulence like airplanes do.

Now IF it had done curly cue's -- That would be really

Maybe it's shaped like a maple leaf seedling?
http://commons.wikimedia.org/wiki/File:Maple-seed.jpg

This trail indeed looks like the path of a knuckleball. It is easier to see on a volleyball court when a fast service with no rotation is coming at you. The wobble can easily be as great as the diameter of the ball, and that is at relatively slow speeds. I doubt that either the wind or the observer is going to oscillate in a similar manner. So my vote is for a non-rotating, relatively spherical object. Lacing optional.

This image has been widely discussed in the meteoritics community. The consensus (unanimous as far as I've seen) is that the camera got jarred by wind or maybe an animal. The same effect has been seen on other images where that happened.

"meteors are candidates for seeding life on Earth...."

That is the old sci-fi excuse of long, long ago and far, far away, which avoids the question of where and when life first appeared. It is lost in distance and time, hopelessy inexplicable. Why not postulate abiogenesis? Maybe that happens frequently. Maybe it happened for the millionth time in a swamp in Louisiana last Thursday.

Doug Chandler

besides the effects described, the body rotated.

prigator@aol.com wrote:"meteors are candidates for seeding life on Earth...."

That is the old sci-fi excuse of long, long ago and far, far away, which avoids the question of where and when life first appeared. It is lost in distance and time, hopelessy inexplicable. Why not postulate abiogenesis? Maybe that happens frequently. Maybe it happened for the millionth time in a swamp in Louisiana last Thursday.

Even abiogenesis needs something to work with. Common thought now is that the building blocks of life came from meteoroids, not life itself.

APOD wrote:are candidates to have seeded Earth with prebiotic molecules that allowed for the development of life

My guess: Rapidly spinning Earth satellite collision debris burning up on reentry.

Notice how the meteor's train wobbles quite signifcantly at the begining but has smoothed out by the end. To me. this would indicate an irregular shaped body that has undergone ablation to become less irregular and therefore more stable. I'm not too sure about an animal or the wind knocking the camera/camera mount because that we be just too coincidental - to have the camera bumped in the same split second it took for the meteor to flash across the sky (although I wouldn't rule it out entirely).

Chris Peterson wrote:This image has been widely discussed in the meteoritics community. The consensus (unanimous as far as I've seen) is that the camera got jarred by wind or maybe an animal. The same effect has been seen on other images where that happened.

What is interesting to me is that it looks like a decaying sine wave. Like it was 'rung like a bell' and the sound dies out. What would happen if the object left a trail and also produced a 'sonic boom''? Could the pressure waves from the 'boom' distort the trail in a regular pattern, decreasing over distance?

Occam and I postulate atmospheric distortion/aberration

Looks like dampening vibration caused by camera shake. Notice symmetrical blur marks around star images.

Jarred Camera? There doesn't seem to be any evidence of that in the stars.
Anyone who has thrown rocks off a high cliff will have seen this effect - though I've not managed a hypersonic launch yet!
Anyone know where I can get hold of some open-source software for analysing hypersonic 'flight' or is it 'military secret' stuff.

There seems to be another fainter streak to the right of the photo. Is it the same meteor, or is it another streak?

For such a short event, it seems unlikely that camera wobble would explain the effect. I agree with a couple of the other posters in that the shape and/or rotation of the meteor as it entered the atmosphere would be a good possibility.

Is the meteor in earth's atmosphere? How do we know that?

Thanks,
Smita

Chris Peterson wrote:This image has been widely discussed in the meteoritics community. The consensus (unanimous as far as I've seen) is that the camera got jarred by wind or maybe an animal. The same effect has been seen on other images where that happened.

I'am with you. The first thing I thought when I saw this picture was camera wobble. You don't notice this in the stars because of the relatively short exposure, but will show up in a fast moving object like a meteor.

When I was a kid living in California not far from Vandenberg Air Force Base, I saw several re-entries of rocket parts that took non-rectilinear paths.

I'm going with a jarred camera myself (rather than the tripod). Take a close look at the stars in the image. All appear to have a faint wing shape to either side which points towards the center of the frame.

After years of observing hundreds of meteors, I have once seen a twisting entry. Leaves a strong impression on your senses. It looked even more pronounced than the one in the photo and it was a retrograde orbit entry. No idea why it would spiral like it did.

Readout of a interlaced ccd's can at times give very similar pattern, was the camera working in an interlaced mode ?

Two "meteor trails," both with the same spiral twist, appear in the photo. This would tend to rule out a rotating meteor since they are relatively uncommon; but the 2nd one looks so much like the 1st that it may be an aberration, maybe caused by the lens ... or a hoax. In any case, the distant observatory is blurry; but a closer structure is sharper ... so the camera is not properly focused for distant objects (stars and satellites). The trails appear to display a sort of dampened sine wave with a relatively constant period ... like a "ping" on something with a resonant frequency ... like the tripod holding the camera. The distant star trails tend to lead one to believe that the exposure was taken of something moving slower than a meteor ... perhaps an old man-made, defunct, rotating satellite as it orbits the Earth with sunlight reflecting from it. Why would such an object show a dampened wave instead of a constant-amplitude wave? Maybe because it's trajectory is changing as it accelerates toward the earth to its destruction?