One has to think the extreme elements—or lack thereof—would wreck havoc on electrical systems and other mechanisms within a device. How exactly are these probes and robots able to handle the varying conditions to which they are exposed?
In: Technology
You’ve got to worry about 2 things basically – extreme temperatures, and radiation. Temperature isn’t hard to manage. Spacecraft are covered in very efficient layers of insulating materials to keep internal temperatures within reasonable ranges. They can also have radiators or heaters to keep things from getting too hot or too cold.
Radiation is harder to manage, since full radiation shielding is heavy, and you can’t really afford to have extra weight when going to space. The most critical systems will have *some* radiation shielding, and all electronic components will be radiation hardened.
Since it costs millions of dollars to send these out they are built with the best money can buy when it comes to materials. Also they generally have teams of top engineers working around the clock on them to prep them and design them specifically to withstand these things. Even still these things can fail and do often break down over time.
they’re designed to, you’re not sending your multi-million dollar satellite into space unless you know it can handle it (and sometimes even then it doesn’t, missions do fail)
* temperature. space can be very cold or very hot, whether you’re in direct sunlight or not. lack of air makes it very difficult to spread heat around, fans aren’t gonna work obviously. satellites components are designed to sink heat into the frame of the satellite where they’re mounted, or through metal pipes to a radiator, etc. thermal blankets keep outside heat out and inside heat in, maintaining the proper temperature. some vehicles use radioisotope heat units to generate heat through radioactive decay to protect deep space or planetary probes that deal with extreme cold. the designers figure out how much heat their satellite bus can sink and budget that out to various components, the suppliers have to meet those requirements to get their boxes on the satellite.
* radiation. radiation will fuck your electronics up. individual particles can damage transistors and blow out a component, or alter the memory on your computer, making it do unexpected things (this can happen on earth too, once in… scotland? a cosmic radiation upset caused an election computer to register hundreds of extra votes. you can put plating on your components to block radiation, or use rad-hard parts, that resist radiation or can correct problems caused by it. components are rated for single-event effects, caused by individual particles, total ionizing dose, which measures performance degradation over time from ionizing radiation, ELDRS, which is sensitivity to smaller doses of radiation, and other shit. eventually radiation will kill something or other on your satellite, but you know how long your mission is and you pick parts accordingly.
* shock etc. being launched into space is pretty rough. components and wiring is “staked” with epoxy so it doesn’t move around. you use rugged parts that aren’t going to break under physical stress. you build a sturdy chassis. you drop your boxes, shake them around, hit them with stuff, and see how much they can handle before they stop working. if they can handle the forces applied in a rocket launch, planetary landing, or whatever you’re doing with them, then you can use them.
there’s other weird shit, like outgassing (stuff like epoxy and glue releasing dissolved gasses or moisture in a vacuum, you pick materials that don’t do it, and you bake your parts so they’re moisture-free), multipaction (where electrons multiply inside your radio devices and blow them out), aliens, etc.
but the short answer is that you pick parts that can survive the environments you’re going to deal with (e.g. a satellite in medium orbit is going to take way more radiation than one in low earth orbit, so you need stronger hardening, a deep space probe is going to need to deal with cold, a lander with shock and vibration, etc.), you build a test box first and beat the shit out of it to confirm it can survive, and you don’t put anything on your satellite that you’re not 99.999% sure will survive your environments.
also redundancy. if a part failing can blow the whole mission, you probably have more than one. the space launch system has three flight computers, since losing the flight computer means you have to terminate the flight. nobody wants to be the guy who blew up a crew of astronauts
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