Greetings, gang,
Below is a write-up I did on asteroids (specifically as they apply to
the Sol system, but imminently applicable to just about any star system that
vaguely resembles ours - i.e., has a few gas giants and debris orbiting
the parent star) a few years ago in response to some questions about asteroids
on the gaming table. Since that time the number of asteroids discovered has
gone up, though not by a lot, and the number of *significantly* *sized*
asteroids hasn't really increased at all. So for all intents and purposes,
this study is quite valid for gaming in an asteroid field (you can modify your
own asteroid field as you see fit,
however; if you want a super-dense field where you have a dozen
asteroids on the table, don't let me stop you! you can always call it a
localized
phenomenon or something ;-). I hope the numbers will illustrate why
asteroid fields shouldn't be a big deal for FT craft to fly through. I don't
recall who initiated the question from the FT list. Maybe he is still out
there and will remember this?
Now in response to Ryan's note about how NASA gets all jittery when one of
their spacecraft goes through the field, remember that 1) NASA spacecraft are
fairly autonomous and have extremely limited maneuverability (unlike FT
ships), 2) they don't have active detection devices (unlike FT ships), and 3)
stuck here on Earth we haven't had the opportunity, time, or ability to chart
anywhere near the number of asteroids (large or small) that would be known in
the FT Universe.
Note: I get a little tirade going in the write-up. I was suffering from
dealing with Hollywood (and general media) stupidity on things
space-based (I still do, btw ;-).
Mk
[quoted original message omitted]
Indy,
Very nice. I appreciate your numbers.
However, something as small as a marble could cause a major problem when you
start approaching Oerjan speeds.
At a movement rate of 30 (and I think that this would be approached if jump
points are fairly far out), would be
30,000km/15 min. or 33.3km/second. Even at this rate it
would take over 52 days to cross an AU (~150,000,000km). So I would expect
speeds to be much higher (constant
acceleration/deceleration).
At this speed even a marble sized rock could present enough of a danger to not
be ignored. How many marble sized asteroids are there in the belt? Even in
2100, will we have mapped ALL of these? And how will it keep updated as the
gravitational effects of planets, other asteroids, comets, and ships effect it
(let alone a collision that would send it off at a new velocity and course)?
Now if you are relying on active sensors that have a range of 72mu to identify
something as large as ships, at what range would it detect a marble sized
chunk of rock that is not radiating EM (yes I know that detection and
identification are different, but what is the size of the characteristics that
are measured to identify a ship)? How quickly would you be able to react? How
quickly could a ship maneuver? How fast would you be willing to go?
---
Brian Bell bbell1@insight.rr.com ICQ: 12848051 AIM: Rlyehable YIM: Rlyehable
The Full Thrust Ship Registry:
http://www.ftsr.org
---
[quoted original message omitted]
> On Tue, 7 Aug 2001, Bell, Brian K (Contractor) wrote:
> Indy,
Yep.
> At a movement rate of 30 (and I think that this would
OR the jump points will have to be moved in closer. People might have to
adjust their PSBs accordingly, depending on what they want to accept. It's
very easy to forget just how BIG space is, and just how FAR apart things are.
I should dig up my astrolab from way back which illustrated this emphatically
by setting Jupiter equal to a basketball or something similar and showing how
far apart the various
objects in the solar system are wrt one another - or if
you're road-tripping through West Virginia and stop by the
Green Bank radio observatory, they've laid this out on their lands already. A
few cities have also done this (Boston, I believe, and possibly Denver or
Seattle?).
> At this speed even a marble sized rock could present enough
Yep. Hence K'V weaponry. ;-)
> How many marble sized
Nope. And we never will.
> And how will it keep updated as the
Never be able to.* THerefore the easiest solution is to assume that ships are
composed of alloys that can *take* this kind
of punishment in day-to-day space travel (after all, we ARE
talking about ships surviving MT missile hits, where MT missiles
are supposed to have the destructive power equivalent to nukes ;-).
* - K'V weapons being fired in a given solar system will add
to the chaos of this as well ;-)
In addition, if you are going to concern yourself with marble-
sized objects in the asteroid belt, you have to start concerning
yourself with marble-sized objects EVERYWHERE in the solar system -
and there are a damn good many of them scattered about (space isn't
as empty as the average person thinks ;-). Then you have all these
comets swinging in and out of the solar system, leaving their little debris
chains (case in point: this coming weekend is the peak of the
famed Perseid Meteor Shower, which has been going on all this week -
see http://www.skypub.com/ for further details).
> Now if you are relying on active sensors that have a range
Dunno. That'll be up to the individual player(s) to decide.
I say, and I speak only for me, there comes a point where you have to ignore
the reality and accept some PSB mechanic that
allows you to do this. For me, marble-sized meteoroids aren't
worth bothering over. I assume ships are built capable of withstanding these
impacts. I abstract these out, much as the 3rd dimension of travel is
abstracted out of the FT movement
system. Makes life so much easier. :-)
> At 9:58 AM -0400 8/7/01, Mark 'Indy' Kochte wrote:
> Never be able to.* THerefore the easiest solution is to assume
One issue is whether or not the detonation of the Nuke is point or proximate
to the ship. If it strikes the ship and detonates, then I'd expect these ships
to be pretty stern stuff. If they are detonating proximate to the ship, then
it isn't as big an issue. You don't get quite the shockwave in space as I
understand it. There isn't an atmosphere to compress to make that wave. You do
of course have nice thermal and radiation effects though.
> On Tue, 7 Aug 2001, Ryan M Gill wrote:
> At 9:58 AM -0400 8/7/01, Mark 'Indy' Kochte wrote:
Yep! I think this was heavily covered in an earlier thread a few months back?
I'm more of a basic grunt astronomer, not a nuclear physicist, so I
stayed pretty much out of it. ;-)
> At 12:15 PM 8/7/01 -0400, Ryan Gill wrote:
> compress to make that wave. You do of course have nice thermal and
Well, you've got to get *something* out of it, or the Orion propulsion system
wouldn't be much use. Although, to be fair, that relied on bombs
exploding within tens of meters to fifty meters of a solid plate, generally
coated with graphite... I'm not sure how thick the plate needed to be, or the
graphite, and (of course) how that would relate to FT era starship hull
and/or armor. The Starflight Handbook is, not unsurprisingly, not the
greatest source of information on how to *destroy* starships.... ^_-
Anyone know more on this?
[quoted original message omitted]
> Well, you've got to get *something* out of it, or the Orion propulsion
The idea was proposed by Stanislaw Ulam in 1955. I'd do a net search for you,
but it's to late.
Project Daedalus, pulsed fusion, was the next step, and was investigated by
the British Interplanetary Society in the 70's. I apologize, in an earlier
email this evening, I mistakenly wrote Project Orion instead of Project
Daedalus. I was going by memory, thought it was wrong, read your email, and
went back to my books to correct myself.