Mariner 4 Alternate Universe, What if...? Options

[nprev]

What if Mariner 4's flyby had occurred right across Tharsis & Coprates Chasma, showing volcanoes & canyons instead of heavily cratered terrain? (I understand that trajectory determinants prevented this from happening, of course, but still...). Do you suppose that Mars exploration would have been thrown into hyperdrive during the heady '60s, perhaps enough to sustain manned efforts beyond Apollo?

Doug, my apologies if this is OT for this section...there seem to be some interesting implications here for the imaginative, though.

[edstrick]

Mariner 2 flew with a lot of luck, but it was the real working prototype (based on Ranger) for the Mariner series, starting in mature form with Mariner Mars 64. The near total success of Mariner 2 proved that the essential design was right, and just needed maturing.

There were two real problems on Mariner 2. The Microwave Radiometer was apparently damaged during launch, I think they suspected a thermal shroud was damaged. One of the 2 channels was greatly reduced in sensitivity, and it's response was actually reversed! The other worked reasonably well. This sort of problem was instrument-specific, of course.

The spacecraft overheated badly, and failed not long after the Venus encounter, quite likely due to the overheating. Getting thermal control "right" took time. Modeling was not adequate, and in-space behavior of materials didn't match predictions as they outgassed, changed color, whatever. Mariner 4 actually carried an engineering experiment, besides it's science instruments and the experimental solar light pressure stabilization paddles. It carried a small set of candidate thermal control "plaques" on the sun-facing side of the main body of the spacecraft, with a temperature sensor behind each one to monitor it's temperature changes relative to predicted values as the mission proceeded.

Teeny-tiny "micro-experiments" like that can often be fitted on missions and return significant value for the future. The Magnets on Mars landers are also "micro-experiments", as was Geoff Landis's (I think) dust accumulation experiment of the Sojourner rover.

[dvandorn]

Mariner 4 actually carried an engineering experiment, besides it's science instruments and the experimental solar light pressure stabilization paddles.

Maybe it's just because I started following space exploration back in the 60s, but I have always been mystified by the negative reaction to "engineering experiments" on board any type of space probe.

I know, we can now use computer models to predict the operation of engineering systems. However, such models are only as accurate as the data input into them. It seems to me that, if an engineer feels the need to gather empirical data to support a model, it should be allowed if at all possible.

Engineering experiments might not return a ton of data about the planets, but they can make possible the next generations of spacecraft that *will* return such data. As such, I think they ought to be embraced and not sneered at...

-the other Doug