[time-nuts] Re: constructing a moon base

[Lux, Jim]

On 9/29/21 8:13 AM, Joseph B. Fitzgerald wrote:
> By the time we get to road building, a pretty robust communications system will be in place.   Given the synchronization requirements of modern digital networks, accurate time will be available just as it is in terrestrial cell phone networks.


Actually, I wouldn't assume this, at least in the next 10 years. There 
are national security and commercial forces at play on Earth that lead 
to robust PNT being available. At the Moon, not so much. No need to do 
midcourse targeting of ICBMs for precision munitions delivery (one 
reason for original GPS).  And there's nothing saying that one would 
move existing cell phone networks (and their timing/frequency 
requirements) to the Moon (the density of cells vs users, for instance).

Pretty much everyone starts out thinking "we'll just take COTS system X 
to the Moon" (be it WiFi, WiMax, Cell phones, or whatever).  The 
justification is usually that you'll reduce development costs because 
you have an existing base of designs and parts.

However, you'll find that there are inevitably, some aspects of being in 
Space or at the Moon that "break" some assumption of the existing 
protocol.  And that's before you get into the need to build this stuff 
with something that can tolerate single event effects, both transient 
and permanent. So all of a sudden, you're not "taking existing 
commercial parts and flying them", so now you're doing some new design, 
which might drive you to simpler approaches (since they're cheaper).

The other problem is that for the foreseeable future, the Moon won't be 
an environment where you can design protocols and features for a 1 or 2 
year life like we do for cellphones, with refreshes of technology as 
needed. It's incredibly expensive to put things on the Moon (and even if 
Elon's wildest dreams come to reality, it's still going to be expensive 
- it's just a mass fraction issue) So you won't have nearly the rapid 
evolution we do with terrestrial systems, or, if we do, there will need 
to be significant backward compatibility.  We won't be able to do the 
Apple approach of "Well, the app doesn't support that old iOS any more, 
buy a new iPad"