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15

Source: Me. I currently work as a systems engineer on JWST. JWST will operating from the 2nd Lagrange Point (aka L2), which is approximately 1.5 million km (or 930,000 miles) past the Earth in Sun-Earth line. This is approximately 4x the distance from the Earth to the Moon. This distance, in addition to its lissajous orbit, ensure it will not encounter ...


6

Yes, it has been used. Not an external dome, though. It's much easier to cover the rover body in insulation blankets (e.g. MLI) than to deploy an external dome. The Lunokhod rovers were covered in insulation. In addition, the lid was open during the lunar day (the inside of the lid was covered in solar cells), but closed at night. Likewise, the solar ...


2

In terms of the electronics themselves many specific devices can operate at quite low temperatures, though any property depending on the physical dimension (resistance and capacitance) will change slightly due contraction. Some however explicitly cannot. Batteries depend on chemical reactions that slow down approaching absolute zero and if all the elements ...


25

If surviving lunar nights are difficult to ensure the survival of the electronics, say on lunar rovers, in the low temperatures, The temperature itself is not the primary reason. Lunar nights are difficult to survive because you have 14 days of darkness. If you want to design a solar-powered rover that can store enough energy to stay warm for 14 days, ...


21

From Status of the JWST Sunshield and Spacecraft found in @Antzi 's answer: Most of the electronics is on the "hot side" but there needs to be some conventional electronics on the cold side (beside the cooled IR sensor chips). Small thermal environments on the cold side are equipped with heaters to provide mini-environments at normal operating temperature ...


7

Update 2019: The Chinese Chang'e 3 mission landed the Yutu rover (meaning "jade rabbit") in December 2013. The rover was mobile for 42 days and communicated for 973 days. Its ground-penetrating radar discovered 9 rock layers, and it photographed a terran eclipse of the Sun. Chang'e 4 landed the Yutu 2 rover on the far side of the moon in January 2019. It ...


2

I emailed Ron Creel, the author of LUROVA, and he was nice enough to get back with an answer. (The email address shown in the presentation linked in the question is obsolete, but it wasn't hard to find a good one.) The LUROVA program was run on a digital computer, specifically the Univac mainframe mentioned in the presentation. Here's an extract from the ...


4

From this Planetary Blog post: Driving on worst-case terrain with no consideration can destroy the wheels quickly: The really bad stuff, it only takes 8 kilometers or so and you can destroy the wheel. This is a wheel that was tested to destruction: As you can see, it's still round, it's coming apart lengthwise and at some point the wheel splits in two....


2

New technologies come along In addition to "each mission's equipment has a different profile" requiring different parameters in the lander or the rover, we also keep developing newer technologies. One of the main problems with Curiosity was that the wheels would get damaged and there being no Martian Jiffy-Lube to go to for repairs, the wheels would ...


12

The question seems to be primarily about rovers, which is covered in Hobbes' answer. However, there have also been a large number of landers, which have seen a fair amount of re-use: The Soviet Mars 2-7 landers of the 1970s were built in identical pairs. Even between the pairs, many components were re-used. The two U.S. Viking landers were essentially ...


43

NASA have deployed 4 rovers to Mars, and are working on the fifth. ESA is working on nr. 6. Sojourner: tiny, limited. Spirit and Opportunity (MER): much larger than Sojourner. No reuse possible. Spirit and Opportunity were identical. Curiosity: much larger than MER. No reuse possible - but it does use technologies proven on MER, like the suspension design. ...


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