Unmanned Exploration

  United States Soviet Union
1957   Sputnik-1
First artificial satellite
1958 Explorer III
Discovered Earth's radiation belt.


1959   Luna 1
USSR Lunar Flyby
1959   Luna 2
USSR Lunar Hard Lander first spacecraft to impact the surface of the moon.
1960 Pioneer 5
USA Solar Monitor
1961   Venera 1 - USSR Venus
1962/3 Mariner 2
USA Venus Flyby
Scanned its surface with infrared and microwave radiometers
1965 Mariner 4
USA Mars Flyby
It returned 22 close-up photos showing a cratered surface.
1965   Zond 3
USSR Lunar Flyby
Returned pictures of the lunar far side.
1966   Luna 9
USSR Lunar Soft Lander
Landed on the lunar surface and returned the first photographs from the surface.
1966 Surveyor 1
USA Lunar Soft Lander
First American soft landing
1967   Venera 4
USSR Venus Atmospheric Probe
1970   Venera 7
USSR Venus Lander
First successful landing of a spacecraft on another planet. It used an external cooling device which allowed it to send back 23 minutes of data.
1970   Luna 17
USSR Lander and Rover
Made lunar landing with an automated Lunokhod 1 rover.
1973 Pioneer 10
USA Jupiter Flyby
Passed 132,250 kilometers from Jupiter's cloud tops. It returned over 500 images of Jupiter and its moons. Also collected data  on Jupiter's magnetic field, trapped charged particles, and solar wind interactions.
1974/95 Pioneer 11
USA Jupiter/Saturn Flyby
Pioneer 11 flew by Jupiter on December 1, 1974. It took pictures and measured Jupiter's intense charged-particle and magnet field environment. On September 1, 1979, Pioneer 11 flew past the outer edge of Saturn's A ring at a range of 3,500 kilometers. It has now left the solar system.
1975 Helios 1
USA & West Germany Solar Probe
Solar probe is in a solar orbit
1975/80 Viking 1 & 2
USA Mars Orbiters/Landers
Both landers had experiments to search for Martian micro-organism. The results of these experiments are still being debated. The landers provided detailed color panoramic views of the Martian terrain. They also monitored the Martian weather.
1977/89 Voyager 2
USA Jupiter/Saturn/Uranus/Neptune Flyby
Flew by Jupiter on July 9, 1979,
Saturn on August 26, 1981,
Uranus on January 24, 1986, and
Neptune on August 24, 1989.
1985 Sakigake
Japan Comet Flyby
Comet Halley flyby took place on March 1, 1986.
1985/90 Giotto
Europe Comet Flyby
Comet Halley flyby took place on March 13, 1986. Giotto was then put into hibernation, and to be re-awoken in 1990. Using a close Earth flyby, its trajectory was changed to allow a close encounter with the Comet Grigg-Skjellerup on July 10th, 1992.
1985/91 Suisei
Japan Comet Flyby
Comet Halley flyby took place on March 8, 1986.
1990 Hubble Space Telescope
USA & Europe Telescope
The Hubble Space Telescope has returned high-resolution images of Mars and the other outer planets of the Solar System.