Discovery Atlantis Enterprise Columbia
Calypso Deimos Leda Phobos
V2 Missile Sputnik 1 WAC Corporal Explorer 1
Kuiper Belt Jupiter Ring System Orbiting Neptune Asteroid Belt
Biplanetary systems Binary planets Twin systems Double planets
Ganymede Callisto Titan Io
Mars Europa Titan Io
The Drake Equation The Sagan Equation The Hoyle Equation The Hawking Equation
93 million km/second 186 million km/second 149 million km/second 299 million km/second
5 7 9 3