My local library has quite a good range of books on the UFO phenomenon. A recent addition is Nick Redfern's "The NASA conspiracies." The Career Press. 2011. Pompton Plains, NJ. ISBN 978-1-60163-67949.
Redfern initially takes a look at the views held by a number of US astronauts, e.g. Gordon Cooper. "...Cooper claimed profound UFO encounters of his own, expressed a solid acceptance that aliens from outside of our solar system were among us, and even delivered noteworthy statements on the UFO controversy to prime and influential movers..." (p.22.)
One suggested explanation for the 1965 "crash" near Kecksburg, Pennsylvania was satellite debris. NASA released Kecksburg-based material in 2003. This was followed, in 2007, by legal action against NASA looking for all records they held on Kecksburg. However, the result was "NASA's curiously absent documentation on Kecksburg." (p.41.) The parallels with the total absence of official documentation on the Australian 1966 Westall case are obvious.
Chapter 5 relates the account of an alleged ex US intelligence contract worker, given the name "John," who claimed to have worked at Area 51. John is said to have been "...given an initial briefing by three men, all displaying official NASA credentials." (p.60.) His role was to maintain historical UFO files, which, of course, he read.
Then follows chapters which concern "...research into specific rumours that NASA had undertaken classified research into potentially lethal alien viruses" (chapter 6); "Firm evidence of the fact that NASA personnel during the early to mid 1970's, were deeply interested in seemingly bona fide UFO encounters" (chapter 7); and the fact that NASA was the recipient of US State Department telegrams on an object which 'landed' in Bolivia (chapter 10.)
Further chapters relate to "...a woman named Sharon, who presently works in a secretarial position at NASA's Kennedy Space Center" and who "...claimed multiple encounters with the Grays (chapter 12); "...a number of official reports that NASA has on file, which relate directly to the UFO controversy tell startling and illuminating stories - particularly those that occurred in the mid to late 1980's and mid 1990's. (chapter 14.) Edgar Mitchell's view "...that the evidence for alien contacts was without doubt overwhelming." (chapter 15.)
Finally, the account of British hacker Gary McKinnon's foray into a NASA "...top-secret space based program in place about which the public and the media know absolutely nothing at all." (chapter 17.)
Redfern's conclusions include an acceptance that the Apollo moon landings "...did go ahead just as NASA has always claimed." (p.203._
"On certain other out-of-this-world controversies however NASA might not be so in the clear as it would undoubtedly prefer to be: the Kecksburg, Pennsylvania affair of 1965, the Bolivian event of 1978, the Roswell-connected words of Apollo astronaut Dr Edgar Mitchell, the issue of lethal alien viruses, and the strange saga of NASA and the chupacabra, some would argue are all prime evidence that NASA may know far more about UFOs and extraterrestrial activity than it cares to publicly admit." (pp203-204.
While I suspect that some of the accounts advanced by some of Redfern's informants, do not hold water; I do like the fact that a lot of his documentation is sourced to files located under FOI.