Symposium on unidentified flying objects: hearings before the Committee on Science and Astronautics, U.S. House of Representatives, Ninetieth Congress, second session, July 29, 1968.

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camera was kept stationary the average angular velocities for the object moving
across the field are 0.039 and 0.031 radians per second. The angular velocities in
these sequences sometimes vary erratically from 0.07 to 0.01 radians per second.
This variation may be attributed in part to camera "jiggling" and in part to the
object's motion. The decrease in average angular velocity could be due to the
object's having regressed between filmings just as was reported by Newhouse.
Also the average image diameter decreases about 30% over the entire film, in-
dicating a possible over-all regression of the objects.
The following tabulation indicates the hypothetical transverse component of
relative velocities and accelerations at various distances. It is noted that the
transverse velocity may be only a fraction of the total velocity so that the
numbers actually indicate minimum values.
If the object's
distance was— Its transverse
velocity was— Its transverse ac-
celeration was— Velocity of
single object was-
100 ft 0.65 ft./sec. or 0.44 m.p.h 0.36 ft./sec.1 or 0.11g 3.8 ft./sec. or 2.7 m.p.h.
1,000 ft 6.5 ft./sec. or 4.4 m.p.h 3.6 ft./sec.1 or 0.11 g 39 ft./sec. or 27 m.p.h.
2,000 ft 13 ft./sec. or 8.8 m.p.h 7.2 ft./sec.1 or 0.22 g 78 ft./sec. or 54 m.p.h.
1 mile 23 m.p.h 0.56 g 135 m.p.h.
5 miles 115 m.p.h 2.8 g 670 m.p.h.
10 miles 230 m.p.h 5.6 g 1,300 m.p.h.
The objects in the "Utah" and "Montana" films can only be correlated on the
basis of two rather weak points. First, their structure, or rather lack of it,
is similar. Thus as shown in the "blow-ups" there are no recognizable differences
between them*. Second, the objects on the "Montana" film are manifestly a
single pair; on the "Utah" film perhaps 30% of the frames show clusters of
objects seemingly also grouped in pairs.
The weather report was obtained by the author from the Airport Station at
Salt Lake City. The nearest station with available data is Corinne which
reported a maximum temperature of 84°, a minimum of 47° and no precipitation.
A high ,pressure cell from the Pacific Northwest spread over Northern Utah
during July 2, the pressure at Tremonton would have a rising trend, the visibility
good, and the winds relatively light. The absence of clouds and the apparently
excellent visibility shown on the films would seem to be in agreement with
this report. Through use of References (2) and (3), the Sun's azimuth N132°E
altitude 65° was computed. No shadows were available to confirm the time of
filming.
The image size being roughly that of the Montana film (a few of the objects
being perhaps 10% larger than the largest on the Montana) the same remarks
as to airplane reflections apply, i.e., they might have been caused by Sun
reflections from airplanes within one to three miles to the observer, although
at these distances they should have been identified as conventional aircraft by
the film or the observer. No specific conclusions as to Sun reflection angles
can be drawn since the line of motion of the objects cannot be confirmed. How-
ever, the reported E to W motion of the UFO's and their passing overhead
coupled with the SE azimuth of the Sun would make the achievement of
optimal Sun reflections rather difficult.
That the images could have been produced by aluminum foil "chaff"** seems
possible, at least on the basis of the images shown, as very intense specular
Sun reflections from ribbons of chaff might flare out to about the size of the
UFO's.
Examination of film frames obtained from the photogrammetric experiment—
reference Analysis of Photographic Material, Serial 01, Appendix II, show
that no significant broadening is produced by fiat white diffuse reflectors such
as birds, bits of paper, etc. at f/16 under the conditions of the filming. Actual
measurements show a slight "bleeding" or flaring of about 10% to 20%.
The rectangular flat white cardboards of the aforementioned experiments repre-
sented very roughly the configuration of birds. The light reflected by such a
surface is probably greater than that from a curved feather surface of a bird.
*The images on the "Utah" film appear to be a little brighter. However, possible varia-
tions in development techniques would not allow quantitative analysis in this regard.
**Bits of aluminum foil dumped overboard by planes, often utilized as a countermeasure
against antiaircraft radar. This material might possibly be in the form of large ribbons
several feet long and several inches across.