Re: superhero space navigation

On Sat, 12 Apr 2008 20:55:54 -0700 (PDT), crs <mytg8@[EMAIL PROTECTED]
> wrote:

>Bryan Derksen  wrote:
>
>[snip]
>
>> 3) Communication. Out at the moon a simple omnidirectional radio set
>> will probably be fine but farther than that will require something
>> directional and it might be difficult keeping it lined up by hand,
>> especially considering light speed delays. Will definitely want to
carry
>> a communication satellite out there at the first opportunity.
>
>Really?  A radio set will work for voice transmission from the earth
>to the moon?

What do you think the Apollo astronauts used? Magic?

You want to pick a frequency that doesn't have trouble penetrating the
ionisphere. And more power generally means a stronger signal, though a
good antenna is at least as important.

But any decent ham who builds his own gear (some still do) could build
and operate an earth-moon capable radio. Probably even do it legally.

>You don't have anything specific in mind, do you, as far as radios?
>I've got a SH plot of my own going(timeline:early 1980s) and my
>superfella protag needs to keep in touch with his cohorts on earth.
><gr>  I should mention he's the only super in this world.
>
>Unfortunately, I'm as ignorant as a stone concerning radio
>communications.  I was looking over the spec book on the LM lander(the
>only thing I could find) and it used a couple of S-band antennas for
>transmission to and from Mission Control.  As I recall they had huge
>complexes on the earth end but hey, that was back in the early '70s.
>If there was a set he could get inexpensively or .... snatch five
>finger discount like...

Well, part of the problem was the available power. They had to keep
eventhing really light.

These days? Well, it'd get a bit spendy, but not outrageous to buy
enough solar cells to provide a kilowatt or two.  Hard part would be
keeping them aimed at the sun (or vice vera if you use a steerable
mirror instead of steerable cell arrays).

Batteries for two weeks of darkness are a problem too, as is
vacuum-proofing everything.

And you have problems with only being able to communicate while the
moon is above the horizon.

With my hero, I'd try dragging one of the old 6 foot(?) sattellite
dishes up there to use as a transmitting antenna. Getting it aimed at
earth is easy enough and I think the beam spread would likely still
cover the entire planet even with the way the moon wobbles thru the
course of the month.

Right there you've got a major advantage given that the antenna on the
LM was at best a foot across.

Later one of the *big* mesh antennas that come as segments would
probably work. I've seen even those offered as "please haul it away"
on Freecycle a time or two.

Transmitter and receiver are going to be more of a problem.

Ignoring vacuum and other environmental conditions, you'll probably
want ham gear, it's relatively cheap, well made, and you can get
licensed with fewer questions. More study and work, but less inquiries
as to what you are doing and why you want it.

I do have to wonder what the FCC would have to say about a ham
operating from the moon. Of course, the person on the moon could just
ignore the FCC as they don't exactly have jurisdiction, and if he
operates responsibly, they really wouldn't have a legitimate
complaint.

Other than solar cells, another thought might be a steam generator
using mirrors to heat a boiler.

The radiator for condensing the steam will be a problem as it needs to
be shaded and have a fair bit of area (or be a bunch of pipes buried
deep enough that the temp of the regolith is fairly constant).

Though the buried pipes will have some problems as the heat won't
conduct well to the regolith due to the vacuum between the grains.

But a radiator in the "dark" is going to have problems with the
working fluid freezing.