Unfortunately, the former astronaut is part of the continuing alien cover story. As someone who has studied this subject for many years, the Americans have two distinct explanations for UFOs: they don’t exist or they are from outer space. In 1969, the Condon Report was published in book form, which I own. The explanation? They don’t exist. Project Blue Book was closed.
A gentlemen who worked for NASA, and who observed UFOs, studied them. He was not allowed to discuss his studies openly. After his death, his book, Unconventional Flying Objects, was published. In it, Paul Hill shows that our current ideas about faster than light travel are incorrect. He is eminently qualified to discuss this subject. He also shows his connection with work done at the A.V. Roe company in Canada on building a disc aircraft for the US Air Force, which was done (he claims it was not).
Both the British and Americans have still secret files on the Phoo Bombs. There are interrogation reports published by the British Intelligence Objectives Subcommittee and the Combined Intelligence Objectives Subcommittee that give enough information to show that research work was captured. But there are still reports filed by various branches of American intelligence that are missing or still classified.