Re: superhero space navigation

On Mon, 07 Apr 2008 02:46:33 -0500, Tim Little
<tim@[EMAIL PROTECTED]
> wrote:

>On 2008-04-07, Leonard Erickson <shadow@[EMAIL PROTECTED]
> wrote:
>> What'm wondering is how someone who can "fly" and survive in outer
>> space would navigate. Assuming no supersenses, of course.
>
>They'd probably want a decent skill in naked-eye astronomy.  How far
>do they need to travel?

Depends on the eventual limits. For now, I'm going to avoid pushing
light-speed much.  Which makes a trip to Pluto a royal pain even if
vacuum & radiation aren't a problem, spending that many hours flying
thru a whole lot of not much is not gonna be fun.

>> I can see visual nabvigation between the earth and the moon. But
>> beyond that getting lost would seem awfully easy.
>
>Yes, Earth/Moon navigation would be pretty trivial.

Being able to clearly see the target for the whole trip helps.

>> And even near earth there are problems. I seem to recall that
>> hand-held GPS units don't work and speeds much above 200 mph.
>
>GPS wouldn't be a lot of use out beyond low orbit.  It really wouldn't
>be needed out there anyway.  If they can find Earth at all, they could
>get within a few hundred km of the desired location just by sight, and
>then use GPS after getting closer.

Well, if nothing else, I'd like an idea as to what a normal handheld
GPS unit would *do* on a trip to low orbit.

I was rather surprised when I looked up the specs and discovered how
high the GPS satellites are.

>> And what will work for interplanetary navigation?
>
>Visual navigation would work, though might not be the most efficient.
>It should be pretty easy to use the stars to get orientation, and
>size/heat from the Sun to get approximate radius.  Then use the
>brighter planets as landmarks.  It should be easy enough to remember
>roughly where they should be in relation to other points of interest,
>just in case of equipment failure.
>
>Finding some particular asteroid or a body like Pluto would present
>something of a challenge without equipment, though.  Even a pair of
>good binoculars and some form of rugged portable computer would help a
>lot.  There are numerous programs that can show how the sky should
>appear from a given location in space at a given time.

I'm suddenly picturing an old laptop running one of the spaceflight
simulator programs. :-)

>So how fast can this superperson fly in space, anyway?  Any
>interplanetary journey is very likely to be extremely tedious.

Well, given that I decided I needed them to be able to make a round
trip to the moon in now more than a couple of hours, prefferably
less...

Time to turnover would be 30 min. Distance is 1.5e8 km

1.5e8 = 0.5 * a *(1800)^2
1.5e8 = 1.62e6 a
a = ~93 m/s^2

Call it 10 gees. To halve the time, it looks like it'd take 370 m/s^2
(~ 40 g)

At the higher accel, it takes about 16 hours to cover 2AU. 
Way boring.

Higher accels can cut things quite a bit.  But that requires more
energy. Even going with the idea that the super is fusion powered, it
gets iffy.

Hell, even total conversion gets iffy. 






>
>
>- Tim