Starship Asterisk*

DC wrote:I am intrigued by the idea that there is some unique reflection in the foreground water that is lost in the other reflections in the water. I think I can still see it in the gaussian blur image posted later. It may take more than photoshop to bring out any possible reflections there.

But what do you make of these apparent wave patterns? I've marked the apparent lightness you describe by encircling it with yellow. The areas circled with red seem to balance this out.



P.S. Edited to show a picture blended with the original so you can see where the shoreline is more clearly. In my original post, it was not clear where the water ended and the land began, making it difficult to tell whether the alleged waves were on land (not good).

Anonymous wrote:Thank you HomeAlOne for your most informative post.

You'll note that in the first sentence of the third paragraph the author makes a distinction that atmospheric drag will cause a reduction of velocity for "most meteorites." I believe what we have here is a meteor of a composition making it an exception to the rule here.

There are documented cases of smaller metallic meteors striking the earth at a velocity that could cause the affects alluded to here.

No, I believe you misunderstand the meaning of the sentence. They state

"Due to atmospheric drag, most meteorites, ranging from a few kilograms up to about 8 tons (7,000 kg), will lose all of their cosmic velocity while still several miles up....Meteoroids of more than about 10 tons (9,000 kg) will retain a portion of their original speed, or cosmic velocity, all the way to the surface....On the very large end of the scale, a meteoroid of 1000 tons (9 x 10^5 kg) would retain about 70% of its cosmic velocity...."

The term "most meteorites" is used in the sense of most meteroites are less than 7,000kg.

I agree that a meteroid with a high proportion of metal will be more likely to survive the stress of transiting the atmosphere, and I agree such a meteoroid will have a lower cross-section for its weight and therefore retain more kinetic energy. but I have seen no calculations that lead me to believe that such a meteroid could impact the Earth's surface at anything other than ballistic speeds (ie purely under the influence of gravity and air resistance) without a) weighing alot and b) vaporising the bulb, lamp, dock, the camera and probably a good portion of Darwin.

Just as a reality check, some 6 - 7% of meteroids are the iron or iron-nickel types. Most meteroids are on elliptical ordits, not hyperbolic, so they most likely originate inside the solar system. Small objects in the solar system are vastly more numerous than large ones, following a power law relating mass to adundance. If this was a fairly common small iron based meteroid behaving in this manner, I would have expected someone to have noticed them before.

The other thing is that air resistance will continue to act on the horizontal component of the meteroid's velocity, acting to produce a more vertical trajectory. The faster your putative meteroid is travelling, the greater the angle from the vertical its trajectory can be. Unfortunately, flattening the trajectory also increases the depth of atmosphere it has to traverse to reach the surface. The photo indicates an approach angle of less than 45 degrees (even assuming its path is not angled towards or away from the camera). So its horizontal velocity component is greater than its vertical component.

Again, someone could plug in some mass, cross-section and initial velocity numbers to see what combination allows a meteroid to survive entry. That will give you a predicted impact mass and velocity and an idea of the sort of energy that will be deposited upon impact. We can then test that prediction against reality. I'm betting if such an event had occured, the evidence would be more than a puff of smoke and a possible flash.

There are too many posts to check if the type of my answer is there, so...

Was it a single flash, I mean: not repeated on the following pictures you took? My thought was going towards the flash of the boat which is parked behind the dock.

How could you find any clues of a post being hit or not (or anything else) if it happened on the boat in the background?

Phileas wrote:There are too many posts to check if the type of my answer is there, so...

Was it a single flash, I mean: not repeated on the following pictures you took? My thought was going towards the flash of the boat which is parked behind the dock.

How could you find any clues of a post being hit or not (or anything else) if it happened on the boat in the background?

The 'streak' and 'flash' appeared on only one pic. No evidence has been found on the pic 15 seconds before or 15 seconds after.

The post has been examined. No damage to anything is obvious. The lamp is not working, but then we do not know if it was working beforehand.

Maybe there's a security video camera that watches the wharf that shows the lamp before and after, though I imagine its long since been taped over.

The lightness I think I am seeing in this picture goes the other way, which I've circled in purple

This is a double diff image. It starts with two diff images centered around neutral gray, one of before/central, the other of central/after. Then those are diffed against each other. The idea is to enhance the primary differences, and average out any wave reflection differences, hopefully enhancing any forground reflections in the water. I don't see any evidence of such reflections, but I want to try another approach later.

Also, this image shows the flash and reflection/smoke have different colors, which I don't see as well accounted for in the bug theory.

This is from the same enhanced diff on page 83, showing the trail going into the water.

http://homepage.mac.com/davidbcarlisle/StartOfTrail.jpg

Try again:

Also, in the double diff image, the yellow flash seems to have two parts, a brighter lower part, with a slight division then a dimmer upper part, the upper part being slightly enlongated in the direction of the trail.

HomeAlOne, sorry I didn't mean to post anonymously - just forgot to fill in the username.

you wrote:

No, I believe you misunderstand the meaning of the sentence. They state


Quote:

"Due to atmospheric drag, most meteorites, ranging from a few kilograms up to about 8 tons (7,000 kg), will lose all of their cosmic velocity while still several miles up....Meteoroids of more than about 10 tons (9,000 kg) will retain a portion of their original speed, or cosmic velocity, all the way to the surface....On the very large end of the scale, a meteoroid of 1000 tons (9 x 10^5 kg) would retain about 70% of its cosmic velocity...."

I don't believe I'm misunderstanding the sentence. It states "most meteorites, ranging from a few kilograms up to about 8 tons (7,000 kg)... Last time I checked, a kilogram equals approximately 2.2 lbs., which is to say most meteorites ranging from just under 10 lbs. perhaps? This would be quite a small meteor and, if it could maintain its speed due to composition and what ever other factors may apply, and was to hit the water surface at sufficient speed and at the angle indicated it could have easily caused a splash such as the one shown and without "a) weighing alot and b) vaporising the bulb, lamp, dock, the camera and probably a good portion of Darwin."

One more thought. Someone probably mentioned this in the past 80 pages. But if you use guidelines to mark the top of the lamppost in the before/after images, then use those guidelines in the center image, the flash is not centered at the top of the post.

DC wrote:This is a double diff image. It starts with two diff images centered around neutral gray, one of before/central, the other of central/after. Then those are diffed against each other. The idea is to enhance the primary differences, and average out any wave reflection differences, hopefully enhancing any forground reflections in the water. I don't see any evidence of such reflections, but I want to try another approach later.

Also, this image shows the flash and reflection/smoke have different colors, which I don't see as well accounted for in the bug theory.

I guess I don't understand. If I follow your description, it sounds like what you're doing is (Before-Event) - (Event-After). When I try this, I get essentially what I get with Before-After -- the event detail cancels itself out in the math. I was careful to not do the diff backwards, so I don't understand why this is happening. Seems like one of the first diff images should show a dark streak and light flash. The other should have light streak and dark flash. Then I diff those. Maybe if I just invert one....

When you said centered on grey, what did you mean? How did you accomplish that?

Another thing we must be cognizant of is that over the 30 seconds in question, the clouds have been growing and contribute to an overall brightening of the water.

DC wrote:Also, this image shows the flash and reflection/smoke have different colors, which I don't see as well accounted for in the bug theory.

This has been accounted for, but you have to look way back to page 56, where I posted sample images of insects that have coloration that would result in the pattern shown. Note that this images were not intended to represent the species in the photo but were meant to show what is possible. At the time of that posting, it was not known if the flash wish 1st curtain or 2nd curtain sync, which would have to be known in order to determine which end of the insect had the yellow coloration. That's why there are pictures of black bugs with yellow abdomens and also black bugs with yellow thoraxes.

In any case, the wings are transparent so show up relatively blue, since the camera flash is very blue compared to a sunset, which is supplying the ambient light. The yellow light can be explained by the pollen or other yellow coloring on an insect. Iridescent insects are known to occur in the area. The carpenter bee pictured is also known in the area. It would be somewhat coincidental if the color of the pollen matched the color of the sky. On the other hand, the sky has a huge range of colors, so perhaps that's not so coincidental after all.

Maybe I did my math wrong on my grey diffs. I'll have to think it through again. What I eventually want, though I can't do it in my image processing program, is ((before + after)/2 - event) + 128

I don't think my image processing program can do a correct diff the way I want it. Normally it seems to do a ABS(A-B) because it cannot return a negative difference. (ABS = Absolute Value) The first time I tried to get around that, by effectively adding 128, some values were clipped at either 0 or 255. The second time I tried to get around that, as I recall, I used the curves dialog to push one image (0-255) into (64-255) and the other into (0 - 191), then did a diff on those, which I thought was then centered on neutral gray with no clipping. I used those gray diffs to do the above double diff.

I think the geometry of this image is too simple to be an insect.

I think its Patrick Moore on re-entry

Ed in Oregon wrote:

hazeii3 wrote: The wing beat signal would, if present, be somewhere close to the left edge (on the full size image, each pixel represents about 10.75Hz, so a 200Hz flap would be about 18 pixels in from the left edge).

Haze(ii3) and Victor,
I call to your attention that there is a peak in that FFT at about 160 Hz (15 pixels in from the left) and again at 480 Hz (45 pixels in). The 480 Hz peak is the third harmonic of the 160 Hz. It is reasonable that the 1st and 3rd harmonics would show up like this, as a wing beat would not show on the image as a sine wave, but as something a lot more like a square wave, or series of pulses, thus the odd harmonics would show up quite strongly. I think the bee is buzzing at about 160 Hz. There aren't any other peaks in that region of the FFT.

It's a good point about the harmonics, in fact you can easily see what measures as the 2nd harmonic on the FFT's I did as a cross-check of the approach (the test image I used is shown below, you can see the corresponding sum of FFTs here - also see the 3D version where a whole raft of higher harmonics are evident). I've added this link to the relevant part of my work page if you want more background info.



The peaks could just be noise though; the image you're referring to is after all based of the FFT's of just two pixel strips (one outside and one inside the wing shadow). I'll try summing the FFT's of pixel strips inside the shadow area and an equal number of FFT's outside, then subtract them out; if it's a real peak that should make it clearer.

One could search the FFT outputs for any excess at harmonically-related frequencies with the peak harmonic in the 100Hz to 200Hz range, I suppose; however, there are going to be loads of strong harmonics caused by the cloud edges crossing the trail (this is the reason the first two FFT bins are not shown - if they were, they'd be off the top of the screen).

Are you having a problem with the color of the CONTRAIL and possibly it's duration? The contrail you see is the actual contrail, NOT a shadow of a contrail. Apparently, the color of the contrail can be GREY and it's duration can be SHORT. Please read the info on this URL:

http://www.vnwa.com/Oncourse/Articles/Contrails.htm

DC wrote:Maybe I did my math wrong on my grey diffs. I'll have to think it through again. What I eventually want, though I can't do it in my image processing program, is ((before + after)/2 - event) + 128

That looks like my original diff image.

1. Before + After normal blending.
2. Adjust contrast -50%.
3. Paste event.
4. Adjust event contrast -50%.
5. Use difference blending.
6. Adjust brightness (although here I think there is a difference or I don't understand Photoshops difference tool).

I think I'll try in Paintshop pro, whose math functions are easier to understand.

Bob Peterson wrote:Are you having a problem with the color of the CONTRAIL and possibly it's duration? The contrail you see is the actual contrail, NOT a shadow of a contrail. Apparently, the color of the contrail can be GREY and it's duration can be SHORT.

The problems with the "contrail" are that it ends below the horizon, is uniformly thick over its entire length, and has completely dissapated in 15 seconds.

We know it looks like a contrail, but the geometry is all wrong for it actually be one.

Bob Peterson wrote:Are you having a problem with the color of the CONTRAIL and possibly it's duration? The contrail you see is the actual contrail, NOT a shadow of a contrail. Apparently, the color of the contrail can be GREY and it's duration can be SHORT. Please read the info on this URL:

http://www.vnwa.com/Oncourse/Articles/Contrails.htm

But this doesn't explain why the contrail goes below the horizon -- even below the distant shoreline level, all the way to the point of the flash.

I, too, have seen this kind of phenomenon. I asked a NASA scientist to explain a similar occurance I'd seen and he described it as a crepusuclar ray. I could swear that the one I'd observed in the 1980s in Maryland was on a perfectly clear day, but he assured me that the crepuscular ray was caused by sunlight obscured or otherwise interfered with by a cloud or other atmosphereic pehneomena elsehwere -- perhaps out of my view.

DC wrote:Maybe I did my math wrong on my grey diffs. I'll have to think it through again. What I eventually want, though I can't do it in my image processing program, is ((before + after)/2 - event) + 128

OK. Paintshop Pro works because it has diff AND subtract. But I had to modify your formula a bit to avoid clipping:

1. Average Before and After (call it mean)
2. Mean -50% contrast
3. Event -50% contrast
4. Mean +64 (128 results in clipping)
5. Mean minus Event
6. Negative image (because I think you got the sign backwards if you want the bright spot to look like a bright spot)
7. Adjust histogram



Again, I see a bright spot, but as before, it's clearly bounded by dark spots that offset it.

But wait! Is that another insect trail? Look about midway between our event flash and the top of the picture. There's a dark spot there. That dark spot seems to be a change in direction of a trajectory going up and to the left and down and to the right. Do you see it?