Re: superhero space navigation

On 7 apr, 09:04, Leonard Erickson <sha...@[EMAIL PROTECTED]
> wrote:
> On Mon, 7 Apr 2008 04:14:29 +0000 (UTC), Andrew Plotkin
>
>
>
> <erkyr...@[EMAIL PROTECTED]
> wrote:
> >Here, Leonard Erickson <sha...@[EMAIL PROTECTED]
> wrote:
> >> Ok, I've been playing with a story idea involving superpowers. (Yeah,
> >> I know, not exactly hard sf)
>
> >> What'm wondering is how someone who can "fly" and survive in outer
> >> space would navigate. Assuming no supersenses, of course.
>
> >> I can see visual nabvigation between the earth and the moon. But
> >> beyond that getting lost would seem awfully easy.
>
> >Visual navigation should work well for planets out to Saturn, if the
> >person has even a rough diagram of where all the planets are vs the
> >background constellations.
>
> >If you're lost, head towards the sun. Now look towards the appropriate
> >constellation. The bright thing is a planet. (With the sun at your
> >back, everything is illuminated in full.)
>
> Alas, the sky is gonna be a *lot* more cluttered. I seem to recall
> that outside the atmosphere something like double the number of stars
> will be naked eye visible.
>
Yes, but those which are not naked eye visible in atmosphere are those
which are not visible because they are visibly dimmer than the others.
You can still pick out the constellations of the brighter stars.

Jupiter is always noticeably brighter than all stars. Mars, Venus,
Earth, Mercury depend on where you are. Saturn is among the brighter
stars. But the stars are, well, fixed stars. Find the zodiac. Any
stars which do not belong are planets.

> But assuming that can be dealt with, I guess I'll have to see what
> sort of astronomy programs are available for older handhelds (the
> super in question is a teen and doesn't have a lot of money to spare,
> so it'll be older or cheap gear)
>
Or you can use paper starmap. Or the memory of night sky.

> > It will help to carry something to measure the angular size of the
> >sun. A narrow metal wedge, calibrated for arms'-length, would be good
> >enough.

Something which can easily be at arm=B4s length and come in handy is,
well, hand.

You just need to know whether you're a decent distance inside
> >the orbit of (whichever planet you're aiming for).
>
> Fortunately, part of the "able to survive in space includes protection
> against radiation *including* overly bright light. So the super can
> just look at the sun and use a ruler or something.
>
He will not need to. He can look away from the sun and look at his own
shadow on the ruler, or hand. The width of the penumbra would give the
size of the light source.

> Hmmm. Come to thing of it, the old medieval "cross staff" navigational
> tool might prove useful for measuring angles. And it's cheap and easy
> to make. Thanks.
>
> I do wonder what a normal GPS will do in low orbit (I know the
> satellites are about halfway to geosynch, so they'll still be giving
> useful data).