[meteorite-list] Mystery object in photo

From: Sterling K. Webb <kelly_at_meteoritecentral.com>
Date: Wed Dec 8 05:23:30 2004
Message-ID: <41B6D5FC.EC0F3B5D_at_bhil.com>

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
Received on Wed 08 Dec 2004 05:22:53 AM PST