> Otto Frisch remembers that his friend Fritz Houtermans [..] proposed the popular theory that "these people were really visitors from Mars"
His Wikipedia article goes into more details:
> Houtermans had a great sense of humor. Many have commented on this, and one of his colleagues, Haro von Buttlar, collected stories told by Houtermans and privately published them in a book with more than 40 pages. One story purports to explain the contributions of seven of the twentieth century's most exceptional scientists, Theodore von Kármán, George de Hevesy, Michael Polanyi, Leó Szilárd, Eugene Wigner, John von Neumann, and Edward Teller, all Hungarians. According to Houtermans, they are Martians, who are afraid that their accents will give them away, so they masquerade as Hungarians, i.e., people unable to speak any language but Hungarian without an accent.