TOOLSicon.jpg (5338 bytes) Exploring The Planets
Tools Of Exploration

Probes and Fly-by Spacecraft

The easiest and least expensive missions to other planetary bodies were those in which the spacecraft hit or just missed (flew by) the planet. Because such a spacecraft spends less than a few hours near the planet and observes only a small area, the amount of information these missions send back to Earth is limited. Still, this information is richer in detail than our Earth-bound views.

 

Luna 3

LUNA 3
Image of Luna 3 on its assembly dolly.
Luna 3 was the first spacecraft to view the far side of the Moon. Photographs suggested that the far side was very different from the familiar Earth-facing near side of the Moon.   Dark lava-filled mare are rare on the Moon's heavily cratered far side.


Ranger

The mission of Rangers VI through IX was to take close-up photographs of the lunar surface. These spacecraft were launched between January 30, 1964, and March 21, 1965. Each Ranger spacecraft carried six television cameras. Pictures were transmitted to Earth as the spacecraft plunged toward the Moon at about 2.5 kilometers per second (6000 miles per hour).

Ranger
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Ranger spacecraft on display in Lunar Exploration Vehicles (gallery 112) in the National Air and Space Museum.


Mariner 4

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Nasa Image
  Mariner 4
Mariner 4 was launched November 28, 1964, to take the first close-up observations of the planet Mars. Instruments on board Mariner found that the Martian atmosphere is less than one-tenth as dense as Earth's. As Mariner 4 passed near Mars, it took 22 photographs of the surface. The only landforms seen were craters, and Mars appeared very moonlike. The later flybys, Mariners 6 and 7, viewed only cratered terrain. We now know that Mars is not moonlike at all, but has volcanoes, vast canyons, and geologic evidence of surface water in ancient times.
Related artifacts/info in this and other National Air and Space Museum galleries:
Mariner 4,6,7,9 (to Mars) mission info - Exploring The Planets - Mars.
Mariner 10 spacecraft (to Venus & Mercury) in Beyond The Limits.
Mariner 2 spacecraft (to Venus) in Milestones of Flight.

Pioneer and Voyager

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Pioneer 10 Spacecraft on display in Milestones of Flight gallery 100.
Pioneer 10 and 11 and the Voyager 1 and 2 spacecraft were the first probes designed to study the outer gas giants (Jupiter, Saturn, Neptune, Uranus). Previous spacecraft used solar panels to generate power, but at the distances traveled by Pioneer and Voyager spacecraft,  a long-term energy source created by radioactive decay of plutonium was required. Voyager used a 3.7 meter (10 foot) antenna to transmit data from up to 3 billion kilometers (1.9 billion miles) away from Earth. These spacecraft also carried numerous instruments and experiments to function during the multiple year mission. Voyager 2 provided the only close-up views of Neptune and Uranus available to date. Pioneer 10 became the first spacecraft to travel beyond our Solar System.

Related info in this and other National Air and Space Museum galleries:
Pioneer spacecraft in Milestones of Flight
Voyager spacecraft in Exploring The Planets.

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Voyager Spacecraft on display in Exploring The Planets.

 

Cassini


Artist's rendition courtesy of the Jet Propulsion Laboratory

The next large probe similar to Pioneer and Voyager in design and scope is Cassini. On its journey to Saturn, Cassini joined the Galileo spacecraft in a three month study of Jupiter and its moons during a flyby in December 2000. The result of this partnership was the observation of a new volcanic plume near the north pole of Jupiter's moon, Io. Information from both spacecraft indicated that the new plume was nearly 400 kilometers (250 miles) high and about the same size as a long-lived plume produced by a volcano on Io named Pele. The presence of such a large plume near the pole came as a surprise, since all previously detected plumes have been over equatorial regions and no others have approached Pele's in size.

For more information, see the Cassini Mission home page.

 


Tools of Exploration
Earth-based Observations || Airborne and Orbital Telescopes || Probes and Fly-by Spacecraft
Orbiters || Landers || Rovers || Sample Return

©2002 National Air and Space Museum