Theory 1 is common, understood, reproducible, researched. Countless "event As" have occurred and are confirmed to be caused by Theory 1.

Okay.

Theory 2 has no evidence beyond heresay.

And radar records, and expert testimony, and film footage, and an utter void of alternative explanations.

 >It isn't taken seriously by any scientific journals.

"Libel Suit May Develop From UFO Hassle", Scientific Research, may 13, 1968, pp. 11-12. Baker, Robert M. L., Jr., "The UFO Report: Condon Study Falls Short", Scientific Research, April 14, 1969, p. 41. Popular Science Armagnac, Alden P., "Condon Report on UFOs: Should You Believe It?", Popular Science, April 1969, pp. 72-76. Engineering Opportunities Hersey, Irwin, "UFOs and the Condon Report: Are All the Answers in?", Engineering Opportunities, April 1969, pp. 39-42. McDonald, James E.,"The Dissenting View", Engineering Opportunities, April 1969, p. 33. Science and Mechanics Mallan, Loyd, "The Condon Report: Fact or Fiction?", Science and Mechanics, 40.5, May 1969, pp. 38-40, 86,88,90. Technology Review Hynek, J. Allen, "The UFO Phenomenon: Laugh, Laugh, Study, Study", Technology Review, Vol. 83, No. 7 July 1981, pp. 50-58. Nature Ridpath, Ian, "Interview with J. Allen Hynek", Nature, Vol. 251, October 1974, p. 369. 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Murray, Bruce C.,"Reopening the Question", Science, Vol. 177, August 25, 1972, pp. 688-89. Holden, Constance,"Air Force Bestows on National Archives a Trove for UFOlogists", Science Vol 193, August 20, 1976, pp. 662-663. Physics Today Friedman, S.T., "More on UFO's", Physics Today, P. 97, January 1971. Powers, W. T., " Case for "real" UFO's", Physics Today, P. 14, June, 1970. "Condon Study Rebuts UFOs; Critics Offer Own Version", Physics Today, Vol. 22, Nr. 3, March 1969, p. 67, p. 71. Rothberg, Gerald, "UFOs: Fact or Fiction?", Physics Today, Vol. 22, Nr. 12, December, 1969, pp. 69-71. Hynek, Allen J.,"How to Photograph a UFO", Popular Photography, March 1968, p.69-110-112-114. Journal of Scientific Exploration Brandenburg, John E., DiPietro, Vincent, and Molenaar, Gregory, "The Cydonian Hypothesis", Journal of Scientific Exploration, Vol. 5, No. 1, 1991, pp. 1-27. Bounais, M., "Traumatology as a Potent Tool for Identifying Actual Stresses Elicted by Unidentified Sources: Evidence for Plant Metabolic Disorders in Correlation with a UFO landing", Journal of scientific exploration, Vol. 4, No. 1, 1990, pp. 1-18. Bramley, William, "Can the UFO Extraterrestrial Hypothesis and Vallee Hypotheses Be Reconciled?", Journal of Scientific Exploration, Vol. 6, No. 1, 1992, pp. 3-11. Guerin, Pierre, "A Scientific Analysis of Four Photographs of a Flying Disk Near Lac Chauvet", Journal of Scientific Exploration, Vol. 8, No. 4, 1994, pp. 447-469. Haines, Richard and Vallee, Jacques, "Photo Analysis of an Aerial Disc Over Costa Rica", Journal of Scientific Exploration, Vol. 3, No. 2, 1989, pp. 113-131. Haines, Richard and Vallee, Jacques, "Photo Analysis of an Aerial Disc Over Costa Rica: New Evidence", Journal of Scientific Exploration, Vol. 4, No. 1, 1990, pp. 71-74. Haines, Richard, "Analysis of a UFO Photograph", Journal of Scientific Exploration, Vol. 1, No. 2, 1987, pp. 129-147. Henry, Richard C., "UFOs and NASA", Journal of Scientific Exploration, Vol 2, No. 2, 1988, pp. 93-142. Maccabee, Bruce, "Analysis of the Images of a Cluster of periodically Flashing Lights Filmed Off the Coast of New Zealand", Journal of Scientific Exploration, Vol. 1, No. 2, pp. 149-190, 1987. Maccabee, Bruce, "Strong Magnetic Field Detected Following a Sighting of an Unidentified Flying Object", Journal of Scientific Exploration, Vol. 8, No. 3, 1994, pp. 347-365. Sturrock, Peter, "An Analysis of the Condon Report on the Colorado UFO Project", Vol 1, No. 1, 1987, pp. 75-100. Sturrock, Peter, "Report on a Survey of the Membership of the American Astronomical Society Concerning the UFO Problem", Journal of Scientific Exploration, Vol. 8, No. 1;2;3, 1994, pp. 1-45;153-195;309-346. Swords, Michael, "Could Extraterrestrial Intelligences be Expected to Breathe Our Air?", Journal of Scientific Exploration, Vol. 9, No. 3, 1995, pp. 381-392. Velasco, Jean-Jacques, "Report on the Analysis of Anomalous Physical Traces: The 1981 Trans-en-Provence UFO case", Journal of Scientific Exploration, Vol. 4, No. 1, 1990, pp. 27-48. Vallee, Jacques, "Return to Trans-en-Provence", Journal of Scientific Exploration, Vol. 4, No. 1, 1990, pp. 19-26. Vallee, Jacques, "Five Arguments Against the Extraterrestrial Origin of Unidentified Flying Objects", Journal of Scientific Exploration, Vol. 4, No. 1, 1990, pp. 105-117. Vallee, Jacques, "Towards a Second-Degree Extraterrestrial Theory of UFOs: A Response to Dr. Wood and Prof. Bozhich", Journal of Scientific Exploration, Vol. 5, No. 1, 1991, pp. 113-120. Wood, R., "The Extraterrestrial Hypothesis is Not That Bad", Journal of Scientific Exploration, Vol. 5, No. 1, 1991, pp. 103-112.

 Many proponents of Theory 2 are not mentally stable.

From this article by Harvard psychologist Dr. John E. Mack:

Psychiatric evaluations and psychological studies of abductees, including several of my own cases, have failed to identify consistent psychopathology. Abductees may, of course, suffer from mental and emotional distress as a result of their often traumatic experiences, and a few have been found to have accompanying psychiatric conditions. Many come from troubled family backgrounds. But in no instance has the emotional disorder provided an explanation for the abduction experience.

 Nearly every time Theory 2 is proposed, it is later shown that Theory 1 is actually the case.

Or assumed where not showable (see above).