One or two additional general remarks may be relevant to space ships as "flying objects". The distribution of flying objects is peculiar, to say the least. As far as this writer knows, all incidents have occurred within the United States, whereas visiting space-men could be expected to scatter their visits more or less uniformly over the globe. The small area covered indicates strongly that the flying objects are of Earthly origin, whether physical or psychological.
The lack of purpose apparent in the various episodes is also puzzling. Only one motive can be assigned; that the space-men are "feeling out" our defenses without wanting to be belligerent. If so, they must have been satisfied long ago that we can't catch them. It seems fruitless for them to keep repeating the same experiment.
Conclusions:
Although visits from outer space are believed to be possible, they are believed to be very improbable. In particular, the actions attributed to the "flying objects" reported during 1947 and 1948 seem inconsistent with the requirements for space travel.
Very truly yours,
J. E. Lipp
Missiles Division
JEL:sp
References
1. "Earth, Moon and Planets", by F.L. Whipple, Harvard Books on Astronomy, Blakiston, 1941.
2. "Atoms, Stars and Nebulae", by Goldber., Alter; Harvard Books on Astronomy, Blakiston, 1943.
3. "The Story of Variable Stars", by Campbell and Jacchia, Harvard Books on Astronomy, Blakiston, 1945.
4. "The Milky Way", by Bok and Bok, Harvard Books on Astronomy, Blakiston 1941.
5. Calculated Properties of Hydrogen Propellant at High Temperatures. Data provided to RAND by Dr. Altman, then at JPL. Unpublished.
6. "The Use of Atomic Power for Rockets", by R. Serber, Appendix IV Second Quarterly Report, RA-15004, Douglas Aircraft Co., Inc., Project Rand.
7. "Galaxies", by Shapley, Harlow; Harvard Books on Astronomy, Blakiston 1943.
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