Perry and his students (who formed the Kettering Group along with some other volunteers worldwide) continued their satellite tracking work for a number of years, using only inexpensive shortwave radio equipment and painstakingly using the Doppler effect to deduce the satellites' orbits.
The existence of Plesetsk Cosmodrome was originally kept secret, but it was discovered by British physics teacher Geoffrey Perry and his students, who carefully analyzed the orbit of the Cosmos 112 satellite in 1966 and deduced it had not been launched from Baikonur Cosmodrome.
Katy Perry | Perry Mason | Geoffrey Chaucer | Perry Como | Rick Perry | Perry Mason (TV series) | Perry County, Missouri | Geoffrey Rush | Oliver Hazard Perry | Matthew Perry | Matthew C. Perry | Luke Perry | John Perry Barlow | Tyler Perry | Perry | Geoffrey of Monmouth | Geoffrey Moull | Geoffrey Hill | Perry Farrell | Geoffrey Keezer | Geoffrey de Montbray | Brendan Perry | Perry Ellis | Hollingsworth v. Perry | Geoffrey Wilkinson | Geoffrey Howe | Geoffrey Blainey | William Perry | Richard Perry | Linda Perry |