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Comment by dvdfvo | Hacker News Reader

It is awesome to think that martians would code on their own machines, but information is one of the only things that is free to transport over planets and almost without delay. In reality, due to their scarcity, first settlers will perform exclusively physical tasks, software will be updated and fixed remotely, and repairs will be performed following strict instructions or advice from Earth.

Coding as relaxation is plausible, but mostly for short projects and nothing serious. It is hard to focus on serious mental activity after laborious work.

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but information is one of the only things that is free to transport over planets and almost without delay.

Just FYI, RTT to Mars to between 6 minutes and 44 minutes.

Yes. A difference of 4 orders of magnitude.

It's actually less than one order of magnitude. If it were variable from 6 to 60 then it'd be a full order of magnitude, but never four.

I assume they mean from ~200ms to ~20min (i.e. comparing to Earth RTT), which is indeed 4 orders of magnitude.

I believe he meant transporting information compared to transporting physical goods to Mars. The first takes minutes, the other - hundreds of days.

Yes. I though it was obvious from the context of my parent comment.

I don't think that RTT of this magnitude would create significant merge problems.

> but information is one of the only things that is free to transport over planets

The marginal cost in terms of power may be very small (compared to a rocket), but the infrastructure costs are enormous, and as a result you're severely capacity-constrained.

Current link to Mars Odyssey from DSS 35 in Canberra is 14.22 kbps (roughly equivalent to a modem from 1991).

Satellites are very cheap compared to manned missions. Speed will not be a problem then.

software will be updated and fixed remotely, and repairs will be performed following strict instructions or advice from Earth

Sounds like a major flaw to me. What if communication back to Earth is disrupted? Having the entire mission rely on a communication link is not a good idea. The people on Mars should be totally capable of conducting all manual repairs and bugfixes on their own. All of the software they use to run the entire base should be open source, available in a local Martian repository, and at least two of the people on the planet should be intimately familiar with the codebase and how all of the equipment works.

Ideally, they should also have physical books documenting all of the mission-critical stuff.

It depends on the size of the base. If your population ever broke 10,000 then having a few programs might be a good idea. But, redundant radios are cheap and your probably better off sending an extra doctor / pilot / geologist / engineer / biologist etc for your first few hundred people.

After-all having a working terminal that let's someone code is a hell of a lot more complex and uses a lot more power than a radio.

PS: This ends up getting back to the huge cost benefit of sending rover instead of people. Sure if you ever built up a self sustaining base including the ability to manufacture everything it needs from replacement parts, to CPU's, food, and fuel then sure send people. Until then you don't actually get any redundancy from sending people there.

If every computer data on a Mars mission dies, I think all the colonists aree dead. We aren't anywhere close to the technology to support colonists on Mars without technology. Ergo, "physical books" are just a waste of weight.

If every computer ... dies. Ironically this is also true for Earth. Therefore it is not a concern. :-)

How does that follow? There are billions of computers on Earth. On Mars there may be fewer than one hundred. The odds are not even remotely comparable.

Secondly, if all of the computers on Earth die we can still go outside and breathe the air, drink water from rivers and lakes, gather plants and hunt wild game for food. None of those options are available on Mars. If the computer controlling life support suddenly fails, what options are there to survive? All of this has to be planned for and taken into account. If there is nobody on Mars capable of repairing the life support system (including its software) then they are utterly dependent on the communication link back to Earth.

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