Well it could be because people assumed that anything seen in the sky that couldn't be identified was alien in origin. Its a relatively new theory,
brought on by things such as
Star Jelly.
There was also the tape that (supposedly) was filmed from a NASA shuttle showing a wormlike object above Earth writhing through the atmosphere.
It isn't completely impossible for such creatures to exist considering how life seems to be able to grow in the most bizarre places (search
extremophile in google).
Supposed account and picture of a bioform
Many are believed to look like large, simple organisms, so a worm-like one would fit right in.
The most uneasy mentioning about the mysterious creatures of the sky belongs to researcher Robert Gardner. According to him, a transport aircraft of
the US Air Force took off from an army base in San Diego in the summer of 1939. The plane, carrying 12 passengers aboard, returned to the base in
about an hour, after it had sent an SOS. When servicemen opened the hatch, they saw that all 12 passengers were dead. The commander was the only
person, who stayed alive, but he died in several minutes too. The dead military men had strange burns on their skin, but it did not become possible to
find out their origin and what really happened on board the plane. Investigators determined that the crew and the passengers used their personal guns.
The hull paneling of the plane was damaged with gunshots, as if the people were trying to kill a very fast enemy. Apparently, they failed to kill a
mysterious creature.
Source
[edit on 11/3/07 by JackofBlades]
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