ADA133326 (PDF)

huge spiral UFO has occurred at least three times in the last four
years over northwest China. During the inquiry into these matters,
three main viewpoints have been formed: "the meteor theory", "the
aircraft theory", and "the flying saucer theory".
METEOR THEORY DIFFICULT TO SUPPORT
... (portion of text omitted) ...
According to the meteor theory this UFO was one which followed
the direction of the earth's revolution and passed by the earth on a
diagonal from inside the earth's solar orbit, traveling at a speed of
12km/second and At an altitude of 5000km, headed toward the sun.
On the basis of information such as angle of elevation and appar-
ent angular velocity observed at different locations, the Zijinshan
Astronomical Observatory and the Sichuan UFO Research Association
independently conducted calculations and the results all indicate that
the altitude of the UFO which appeared on 24 Jul 1981 was 500km (±10%),
its speed was several kilometers per second and it traveled along a
reverse orbit which had an included angle of 1120(±5%) with the equa-
tor. The various data of the "meteor theory" have been refuted by
the facts.
SPY SATELLITE IS DOUBTFUL
Flying machines (i.e., aircraft and spacecraft) have always been
a major source of*UFOs.
(portion of text omitted) ...
According to U. S. sources, the airspace above space centers,
missile sites and AF bases has been a common source of UFOs. Counter-
intelligence organizations believe that these are spy planes.
WAS IT A FLYING SAUCER?
Among the materials gathered by the UFO Research Association of
China, there are a number of witness reports to the effect that the
24 July 1981 UFO stopped during its flight and hovered for several
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