||Prospector: An heavy US multirole lunar explorer. Killed by
the manned program Apollo. (NASA image)
You can find more on Prospector in my book on lunar exploration history.
See also the Encyclopedia Astronautica entry for Prospector.
|Surveyor Block II. This was an heavy instrumented
version of Surveyor. Never flown.
Only two instruments, the SMSS robot arm and the alpha ray spectrometer flown on Surveyor Block I.
You can find more on Surveyor Block II in my book on lunar exploration history.
See also the Encyclopedia Astronautica entry for Surveyor Block II.
|This image shows one of the losing proposals for NASA Lunar
Being spin stabilized this is either the Hughes of TRW proposal. Can anybody point out which of the two?
For more on Lunar Orbiter see the Destination Moon NASA book.
|Halley Intercept Mission. This is the solar ion
propulsion version of the US Halley Comet Probe.
However, the United States decided not to built a dedicated probe for Halley Comet exploration.
|Halley solar sail heliogyro, designed by JPL. The entire vehicle was spinning to provide stability, while the blades could be pitched to provide attitude control. (NASA/JPL/Caltech Image)|
|Mars Airplane Mission. 12 hydrazine powered airplanes to be
delivered to Mars in three batches of four by the Space Shuttle using
the Viking aeroshell. The aircraft could
deploy small seismometric stations to the ground. Proposed in 1979 but
The idea of a Mars Airplane is currently again considered by NASA and by ESA, which has built a Martian autogyro prototype. (NASA Image)
|A depiction of a US pre-Voyager Europa lander. No
firm plan for such a probe existed at the time nor exists at this time.
|NASA's Mariner Jupiter Orbiter, also known (unofficially) as Voyager-3, relying heavily on Voyager hardware (note, however, the new orbit insertion nozzle). It became the Galileo Jupiter Orbiter. (NASA Image)|
||I have found this image in the Novosti booklet "L'espace
au service de la science", dating from 1987.
It seems to depict a Phobos mission using a Vega bus (note the solar panels!).
I have no idea whether this is just an artistic license or a real project.
I have not found any reference to such a mission elsewhere. Ideas, anyone? (Drawing by A. Sokolov)
|Kepler ESA Mars Orbiter. This 800 kg mass probe was proposed for launch in 1988 on an Ariane-3. It was to study the Martian atmosphere and magnetosphere and to study the topography using a radar altimeter. Not approved. (ESA Drawing)|
|ISPM (International Solar Polar Mission): two
probes, one European, one American, to fly over the Sun's poles.
Scaled down to become Ulysses. (NASA image)
|VOIR (Venus Orbiting Imaging Radar). A NASA probe. Scaled down to becomeMagellan. (NASA image)|
||An early drawing of the CRAF (Comet Rendez-vous/Asteroid
Fly-by) US probe. In the end, this was to be
a twin probe to Cassini, but was canceled in 1992. (NASA Image)
||CNSR (Comet Nucleus Sample Return). This was to be a cooperation between ESA and NASA. In particular, the US were to have provided the spacecraft bus, the same as CRAF (see above) and Cassini. Scaled down to become Rosetta, to be launched by ESA alone in 2003. (ESA Image)|
|Two images of the proposed
Clementine-2 probe, designed to fire anti-missile impactors against
The original mission plan included fly-bies of asteroids 433 Eros and 4179 Toutatis (LLNL Images)
"never were" Soviet missions at Russianspaceweb.com
Unmanned missions to the Sun, Mercury, Mars and Jupiter
"never were" Mars missions after Viking
Romance to Reality: the Viking Era
For questions, suggestions and comments you can email me