The "Star Trek Chronology" does not hold with this theory, and asserts that Cochrane was an Earth native, who moved to Alpha Centauri later in life (even in "Metamorphosis", before Cochrane identifying himself to the landing party, Dr. McCoy had taken a tricorder scan and determined him to be human). The first edition "Chronology" notes that Cochrane's invention of warp drive must have been at least 200 years before "Where No Man Has Gone Before", and suggests a date of 2061, noting that Cochrane would be 31 that year.