Hi!
Nice picture effect. Wish I thought of that. I only made some analyses on the streaked frame and fast switching between pre-streak-post. I don't think it's a meteorite but it would be fun to find out what it is.
When I saw the 37 pages on the discussion board I didn't bother read them, but then I didn't add any postings either.
I don't get your line of reasoning here. Why should a fluffy snowball be able to make it through the atmosphere at hypersonic speed when an iron wouldn't. An object with specific density 0.01 can't be that strong and the aerodynamic forces acting on an object is only dependant on shape, size, speed and the density of the atmosphere. Have you ever tried to throw a baloon?
If a snowball and an iron ball of the same size and speed hits the atmosphere the snowball would suffer a retardation 10 times higher than the iron ball. I assume the specific density is 0.78 and 7.8 respectively. And even if both survived the snowball would drop slower and more vertical than the iron ball. The retardation (acceleration) is force divided by mass and force is only dependent of size, form, speed and athmospheric pressure.
I will take another look at the pictures tonight but I have a party to go to first so it has to wait.
What I would like to know is how the area around the camera looks. Was it indoor or outside? Has the picture been modified in any way except from the camera default compression algorithm? Was the sequence automatic or did he do it manually?
As I'm a sceptic I need more proof that this isn't just a faked picture. The uniform width of the trail (btw, a shadow from a vapour trail would only look straight if you have the light source straight behind you if it's cast on a warped surface), the look of the explosion, the two symmetric ejectas and that the explosion seems to be in front of the lamp post. They all suggests to me that this is a prank.
Compare it with all the true and unaltered pictures of UFO:s that have
appeared the last fifty years.
The only proof that this isn't an altered picture is the statement from the photographer that it wasn't altered. And that is the easiest explanation of this picture.
Regards, Göran
Sterling K. Webb wrote:
Hi,
At the moment I start to write this, there are 37 PAGES on the "official" discussion site for the mystery photo, and I've read ALL of them. A great deal of it is waste because most posters are not reading the other posts and seem to be unaware of the basic facts of the physical situation. Many theories are being batted about, mostly uselessly:
Film, lens and shutter defects: It wasn't a film camera; it was a digital camera. It does not have the characteristics of a CCD defect. It does not seem to be a fake.
The streak is the shadow of a jet contrail: Since we know the geographic location and the precise time (encoded in the camera data), we can tell that the photo was taken at or just seconds after the setting of the sun, so ANY aerial shadow is a physical impossibility. A depressing number of "contrailists" are professional scientists. Strange phenomena, go away! Sigh. To orient yourself, the camera is facing slightly east of due south. The illumination of the clouds is from the sun below the horizon (the sun is off to the right in the photo). The illumination on the water's surface is reflected "cloudglow."
Exploding light bulb: The local utility has inspected the light pole and lamp housing and found NO PHYSICAL DAMAGE of any kind. While the light bulb was found to be non-operable (burned out), everything was physically intact, no leaked sodium vapor, dents, dings, scratches, broken glass, etc. Additionally, it is a sodium vapor light bulb, which would go bad by cycling off and on, NOT by a terminal flash like an incandescent bulb. Another popular but useless theory.
Ball lightning: Please! Contact Nikola Tesla right away...
Folks hereabouts on the List seem to like the "Bug" theory. Too bad. There are lots of reasons why the bug theory is wrong, but here's the most concise one. In the frame that shows the "terminal flash" (which, in the bug theory, is the bug itself only inches away from the camera and caught by the camera flash unit), when compared with the before and after frames, the waters of the inlet between the pier and the camera brighten very noticeably, as if reflecting the "flash" from the pier, and the near sides of the adjacent light posts brighten to a lesser degree also. The flash is a real source of illumination and is located in the vicinity of the pier. No bugs.
Anyone who has puzzled over the mystery photo should look at: <http://images.isja.org/images/strange_diff_pryde_01.png> This is a "difference" processing, created by subtracting 50% of the "before" frame and 50% of the "after" frame, thus isolating only those features unique to the "impact" frame. It clearly shows: a) the streak in the frame has a definite starting point within the frame,
b) the streak extends to the "flash" and not beyond it, c) the streak is quite uniform in thickness and density, with no taper nor spread and a sharp commencement in the photo, d) the streak has a very slight downward arc, i.e., is responding to the force of gravity, e) nothing in the photo connects the lamp post with the flash; they are merely adjacent. The streak passes in front of the lamp post. (If something had hit the lamp post or light housing, they would have moved or wobbled slightly and hence shown up in the difference analysis, like the leaves on the trees in the left of the difference photo do.) f) further along the track of the "object," in front of the flash is a compact circular shock wavefront from disruption of the "object" and a co-centered sideways-viewed disc of ejecta.
So, we have a physical "object," it was in the frame of view when the exposure started, it's showing up in the photo as dark because it is blocking sunlight reflected off the clouds from reaching the imaging element of the camera. The streak is not emitting light, in other words. It could be a shock tube of water vapor or even smoke particles, but it's not luminous. It is actually faint, blocking only about 5% of the sunlight. There is no way to tell the duration of the event, except to say that it could not have exceeding the exposure time (1/20 second).
Only one individual in these hundreds of posts attempted to scale the event and determine the sizes and physical parameters of things, which was what I was doing, too. A nice comparison. We both chose independently to base our scale on the size of the car parked near the pier. He assumed it was an American-sized car; I assumed it was a smaller Australian-sized car. So our estimates differed by that factor. I think the streak is about 2 meters across and 160 meters long; he thinks 205 meters long, and so forth. I make the velocity of the streaking "object" ~2700 meters per second (Mach 8). This velocity calculation is an average speed and assumes the streak moves for the full 1/20 second; it could be faster; it could be slowing down from a greater velocity. It obviously halts at the flash. The flash itself is about 3 meters across with a bright inner core about 1-1/2 meter across. This bright core, by the way, is brighter in absolute luminosity in this photo than the bright spot in the cloud deck that directly reflects the sun. VERY bright.
Many posts on the List discussed entry angles, vertical or not. Let me just point out that vertical drop only happens after velocity stagnation, and this baby is MOVING! So, angle does not tell us much one way or another. As to whether or not an object could penetrate the atmosphere with this residual velocity but without heating to luminescence... Certainly no stone nor iron, small or large, could do so. The critical parameter is density. A cometary ice particle, fairly small, with a very low density, can penetrate the atmosphere nearly to the surface without excessive heating or braking. Think densities of less than 0.01 gram per cubic centimeter. The argument against this, of course, is that it is a special case and hence less probable. But possible. Cometary particles with densities this low have been observed, although those observed have been smaller particles than this one would have to have been. For those who like to calculate the fall of incoming objects, try an object that ends up as a 3 centimeter ball weighing about 100 milligrams at disruption. Try starting with 10 cm. and 1 gm, or with 30 cm and 10 gm.
There are other indications that this was a physically real event. There are two people sitting on benches on the pier. In the "before" frame, they seem to be turned away from where the flash will be. But in the "after" frame, they are facing the flash point. Something got their attention.
Ignoring the really weird theories (tiny UFO's, particle beam weapons, dark lasers, the CIA, black helicopters, etc.) in the "official" discussion, one popular theory is that this was the launch of a firework or model rocket. PLEASE, if there are any model rocketeers out there who can build a rocket of any kind that can accelerate from a standstill to 5400 meters per second in 1/20 of a second, CALL NASA RIGHT AWAY! We need you.
It's not a conventional meteorite (a stray NWA). It does appear to me to have been something physically "real." You got my two cents worth in the "cometary ice particle" bit. But the "mystery" seems to still be a mystery.
Oh, and they're up to 43 PAGES of "discussion" now.
Sterling K. Webb
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