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The Corkscrew Meteor
startleman writes "Over on Space.com is an interesting image of a corkscrew meteor. 'On Jan. 1, 1986, [Jimmy Westlake] was photographing [Halley's comet] through his homemade 8-inch reflecting telescope..."About one minute into the exposure, I watched a meteor zip through the field of the telescope." When he developed the roll of slide film, he was astounded that '...Crossing the tail of Halley's comet was a corkscrew meteor trail with no fewer than 25 twists in it.' Westlake's photo was never published until today. He wonders if there are others out there."
Although I have never seen it in a photograph, couldn't this have been caused by visual waves caused by the atmosphere? Anyone who has looked through a telescope in (crappy) skies knows that objects appear to oscillate rapidly. I don't doubt that a meteor could travel in such a way as to pick up on this. The reason the stars don't appear in this way is because they are fixed objects in a time lapse photo and are averages of all the waves. -Sean
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Could the image be caused by atmospheric affects? I can think of no reason why a meteor could travel in a corkscrew unless it was gravitationally deviated (and I don't think Halley's is big enough to do that to such a fast moving object).
But what do I know, IANAA(stronomer).
I forget what 8 was for.
Off topic but...Comet Macholz is found right by Pleiades ("seven" star cluster) tonight. I could manage to spot it with a pair of binocular in Boston. It's fairly fuzzy and faint, though.
Assuming it isn't just atmospheric, it looks to me like the meteor is long (like a cylinder) and is rotating at an angle that isn't along one of its axes (which is normal, and causes seasons on earth).
It looks like all the backround stars have some motion blur. Perhaps the telescope wasn't all that steady during the exposure.
...that's an alien Soul Plane?
Come on, how can there NOT be another one there? We like to think we're the greatest thing to happent o the universe since sliced bread. The first time we notice a natural occurence is the first and only time it exists to the general human populace. Given the number of meteors whizzing about throughout the universe, there's no possible way this could be an isolated phenomenon. Let's spend less time on conjecture and more on "Where's the meteor that will wipe out humanity as we know it?"
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I've seen meteors do this, with naked-eye observations during one of the more active fall showers a few years ago. In fact, most of the larger or brighter ones seemed to do it with varying intensity. It's not atmospheric distortion. It's way too periodic.
I've also seen them with second or third order oscillations, making larger spirals like a big, fast, heavy leaf 'fluttering' to the ground.
I just assumed that it was the meteor tumbling like it's probably going to - considering it's not probably not an aerodynamically stable shape - and just spewing and sputtering ablating matter as it burned up.
Why is this a mystery? Anyone that's shot irregular flakes of rocks (or, say, pennies) out of a wrist-rocket or slingshot will see that they behave in much the same way - aerodynamically unstable objects tumbling and spinning from drag as they pass through the atmosphere at high speed.
It may be possible that the photographer simply inadvertantly bumped the scope, causing it to wiggle while a meteor or satallite temporarily flew in view. Normally it would blur the stars also, but if the wiggling happened only during a small percentage of the total exposure time, then the stars may be generally uneffected.
Table-ized A.I.
I, for one, welcome our new meteor-steering corkscrewing overlords.
With the naked eye. I was spending the night at Santa Cruz island, Channel Islands, California. It was in November and we had sailed out there to spend the night. It was very clear that night and dark. No city light (I live in Los Angeles). You could see the Milky Way. Then my friend and I noticed little metior streaks, kinda nice. The I saw this large one, it wasn't the line flash you see all the time. This was slower moving and corkscrew. It traveled across the sky and the trail glowed for a few seconds. I though it was something that happens all the time.
The assumption of a 60 Hz hum and 25 twists implies a total visible travel time of .42 seconds, which seems about right. The fact that the trail isn't more smeared is an indication that the meteor trail is made by a swiftly moving light source that would look like, if we could have taken a very short duration exposure, more like a point source than a bright coma followed by a tail of brightly glowing plasma. The roughly constant production of light along the trajectory and its length suggests that the meteor was a so-called "earth-grazer" (not to be confused with asteroids or comets of the same name) dumping most of its kinetic energy rather high in the atmosphere along an almost horizontal path. Somebody with more time on their hands than I could develop an algorithm, using simple and fairly reliable assumptions (a straight trajectory at at a slowly decelerating velocity, damped sinusoidal oscillation, etc.) to extract a third dimension of information from the photo. In other words, a crude movie of the meteor moving across a backdrop of comet and stars could be made. I find this encoding of an extra dimension on a flat piece of film intriguing. It reminds me of holograms, although they of course encode an extra spacial, not temporal, dimension.
"I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
As the object passes through the atmosfere, it will probally rotate as many suggests - but that must alså mean that the amount of surface that is exposed in front of the meteor and therefore heated to the point of glowing (or burning) changes over time. I do not believe it's a matter of a "skrew" shape.
I believe it's more likely that a meteor will be subject to some level of rotation as it travels.
Another question to all those who have seen this kind of meteor, did the meteor seems to stabilize as it traveled farther in to the atmosfere?
Need to know distance to meteor, speed of meteor and some estimate of field of view. Then calculate the width and length of the "wobbles". Some enterprising physics student could then calculate how much acceleration the object is going through at the top of each arc. I suspect the answer is a very large number.
As an aside, I think the falling leaf/penny analogy is WAY off. Falling leaves are turbulence dominated, whereas this thing is presumably supersonic, leaving its turbulence way behind.
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