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Deep-space probes (Voyager)
Robotic probes visited every planet; Voyager 1 and 2 (launched 1977) toured the outer planets and Voyager 1 entered interstellar space in 2012.
Open in the interactive tree →Mariner 4 flew past Mars in 1965 and Viking landed there in 1976. Voyager 2 is still the only probe to have visited Uranus (1986) and Neptune (1989). Later missions such as Galileo, Cassini, New Horizons and the Mars rovers found oceans under icy moons and ancient water on Mars.
Prerequisites
- Hohmann Transfer Orbits1925Probe trajectories to other planets are planned as Hohmann-type transfers
- Nuclear Physics1938Voyager's power comes from radioisotope generators built on nuclear decay
- Programmable Computer1941
- Information Theory1948Voyager's data links use error-correcting codes from Shannon's information theory
- Error-Correcting Codes1950Voyager's images reached Earth thanks to Golay error-correcting codes
- First satellite (Sputnik)1957
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More in Space & Astronomy · Atomic & Space Age
- First satellite (Sputnik)1957
- Apollo Guidance Computer1961-1969
- First human in space1961
- Pulsars1967
- Moon landing1969
- Black Holes (Cygnus X-1)1971-72
- Space stations1971
- Space Shuttle1981