How well would optical fiber work on the Moon or Mars?

Question

Optical fiber used for data transmission over long distances is usually made from ultra-pure SiO2 and carefully doped with germanium in the core to elevate index of refraction. Fiber amplifiers include Erbium doping which can be optically pumped for in-fiber optical gain.

But that's on Earth where radiation is low and thermal excursions are limited.

If on the Moon or on Mars, how well would standard fiber solutions work for say a 1000 kilometer, high Gbit/sec to 1 Tbit/sec link work? Could cable used for underground runs here work just rolled out on the surface there?

Issues related to physical degradation of the outer protective layers, and to the optical performance of the fiber itself should be addressed independently.

Assume a normal mix of in-line optical amplifiers and less frequent electrical repeaters.

Comments and answers to the question Long, low mass data transfer wire options only touch on optical fiber as an alternative for a relatively short 1 km run on the Moon, but for that, probably a free-space optical connection would be better than a fiber.

GittingGud · Answer 1 · 2019-05-03T06:22:58.110

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Standard commercial optical fibers could be used for data transfer on the Moon or Mars, but they may have a shorter life span than on earth and worse signal quality.

The radiation does have an impact on the molecular bonds of the optical fibers which can cause signal degradation. The phenomena is called "Radiation Induced Attenuation" for which you can find scientific publications on. This means that better signal processing/amplification is needed if long distance will be covered. How much the signal is actually impacted on by the radiation is not known to me. Nevertheless if the weight advantage of optical fibers compared to copper or aluminum and that they are immune to electromagnetic or radio-frequency interference is taken in consideration I would assume they would be a great choice.

But we always have to keep in mind that is does take a lot of effort (and money) until a technology is "flight certified" for space travel and because people don't like to change a running system it might take some time until optical fibers replace normal wires.

This chinese publication seems to be a perfect fit for the topic but I seem unable to download it.

Additionally here is a presentation from CNES (Quality Assurance Department) employees on the topic. Radiation-Induced Attenuation On Commercial Optical Fibers (The presentation slides aren't that informative or high quality)

edited May 03 '19 at 06:22

answered May 03 '19 at 06:03

GittingGud

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Another great answer in progress! A source for "optical fibers are used in space application" would be handy eventually, I'd never heard of that, except as a question: Could multimode (polymer) optical fiber Gigabit Ethernet be a better choice than WiFi inside future satellites? – uhoh May 03 '19 at 06:08
@uhoh I've quickly digged into providing a source and couldn't find anything apart of an airbus concept. I will take it out of my answer as long as there is no source. – GittingGud May 03 '19 at 06:15
It's up to you; ff you are fairly sure that it's true, I'd say leave it in with a parenthetical mention that you're going to look for a source. – uhoh May 03 '19 at 06:18
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@uhoh I'm not sure I have just assumed because I've seen so many papers about optical data transmission in space. But what might be interesting is that there are experiments for manufacturing optical fibers in space. – GittingGud May 03 '19 at 06:21
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Yes that sounds familliar, I thought there was a question here about what things could really benefit from being manufactured in space, I'll keep looking for it. Also, slightly related glass fibers (not yet) in space: How is lunar regolith drawn into “glass fibers” to reinforce lunar concrete in this process? – uhoh May 03 '19 at 06:48
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@uhoh I selected optical systems as a specialization in my bachelor study and I would say that optical fiber manufacturing can benefit from no gravity but I highly doubt that it is remotely worth the effort regarding current launch cost and orbital facilities (even as an experiment). Nevertheless I remember several professors talking about the possibilities and advantages of manufacturing optical components in zero g but I remember lasers being the topic and not optical fibers. – GittingGud May 03 '19 at 07:33
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This is a great answer, but I'm going to hold out for something more definitive. Thanks! – uhoh May 19 '19 at 11:21

How well would optical fiber work on the Moon or Mars?

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