Related by context. Frequent words. (Click for all words.) 57 Soviet cosmonaut Yuri Gagarin 56 Gene Cernan 53 lunar module pilot 51 Astronaut Buzz Aldrin 51 Edwin Buzz Aldrin 48 Buzz Aldrin 47 Frank Borman 47 Gus Grissom 47 spaceflight participant 47 Russian cosmonaut Yuri Malenchenko 47 astronaut Yang Liwei 46 cosmonaut Yuri Gagarin 46 moon 46 Space Shuttle Endeavor 46 Zhai Zhigang 46 Mars 45 Russian Gennady Padalka 45 Yang Liwei 45 NASA astronaut 45 planet Uranus 45 astronaut Buzz Aldrin 45 Space Shuttle Launch 44 orbited Earth 44 astronaut Julie Payette 44 astronaut Sunita Williams 44 moon Charon 44 rover Opportunity 44 NASA Astronaut 44 Sergei Volkov 44 astronaut 44 JPL manages 43 aboard Atlantis 43 Jupiter Saturn 43 Space Shuttle Discovery 43 Owen Garriott 43 Leland Melvin 43 Soyuz capsule carrying 43 Venusian 43 Roberto Vittori 42 Shuttle astronauts 42 Commander Peggy Whitson 42 orbiting 42 Cady Coleman 42 Neil Armstrong 42 Timothy Kopra 42 taikonaut 42 Bearing External Resistance Treadmill 42 Nie Haisheng 42 ISS Expedition 42 spaceship 42 Saturn moons 42 Koichi Wakata 42 Robert Curbeam 42 Julie Payette 42 astronaut Daniel Tani 41 Mission Specialists 41 Space Shuttle Endeavour 41 Apollo missions 41 Alexander Kaleri 41 Peggy Whitson 41 Astronauts 41 spacecraft orbiting 41 Ron Garan 41 Mikhail Tyurin 41 Combined Operational Load 41 Tim Kopra 41 Yuri Malenchenko 41 Astronauts aboard 41 Piers Sellers 41 Messenger spacecraft 40 commander Dominic Gorie 40 Yuri Gagarin 40 taikonauts 40 astronaut Nicole Stott 40 innermost planet 40 Halley Comet 40 Russian cosmonaut Gennady Padalka 40 baseman Clint Barmes 40 Eugene Cernan 40 Moonman 40 Randolph Bresnik 40 Rex Walheim 40 Apollo astronauts 40 Solar Dynamics 40 Flyby 40 Richard Feynman 40 International Space Station 40 commander Peggy Whitson 40 Shenzhou V 40 NASA Cassini 40 comedian Jimmy Fallon 39 Kenneth Bowersox 39 Alan Shepard 39 spacemen 39 astronauts 39 ESA astronaut 39 Nicole Stott 39 Gregory Chamitoff 39 twin rover Spirit 39 spacewalk 39 rovers Spirit