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Gzg-l mailing list
Gzg-l@lists.csua.berkeley.edu
http://lists.csua.berkeley.edu/mailman/listinfo/gzg-lOkay, let's give
this its own thread.
As to Asteroids: I know the real ones are thin. However, for all that, at
pretty much every Con I attend, there's a game with large, dangerous
asteroids. So my reference in the prior thread to 'asteroid racers' was from
popular usage, rather than realistic space simulation. You could substitute
'racers who race around buoys and such' (there was a stargate SG-1
episode in the late seasons that focused around a spaceship race that included
a
close run around the sun and navigating a field of armed range-capable
mines).
So, asteroids should probably really be: Not present on the game table in
numbers or a small hull scrubbbing effect that persists throughout the game.
Nebula: Indy brings them up, but my understanding was they were not very
dense either - not much real risk or damage unlike how they got
portrayed in Wrath of Khan. Aren't they pretty diffuse in real life?
Rings: Indy mentioned rings. What's a realistic estimation of ring densities?
How often do you see asteroids big enough to feature as an FT
obstacle in a ring system? What sort of on-map separation would be at
all close to reality?
Planets can be done, moons can be done (though I doubt both on the same board
without an MU of at least 10K km). Gravity can be very cool
(Can-Am I
at ECC had a nice planet and some awesome gravity and proved that I have done
Titan's Turn....). How small of an entity could reasonably generate FT visible
gravitational effects? The moon should be 3" at 1000 km per MU according to
the link I just visited that was posted in the other discussion. How much
smaller can you get? (Yes, this is a density function, but how small and dense
could you get for a moon or small planetoid?)
Black Hole: What sorts of gravitation would you get from a black hole? Could
one be put on an FT map and have any part of the map be playable by FT
fleets at 1000 km/mu or 10000 km/mu?
Pulsar: In SFB, a pulsar used to emanate damaging waves your shields helped
thin out. Is this at all reasonable? Could a reasonable bit of space terrain
be done with some mechanic like this?
Sphereworld or Ringworld: Planet plus? Could make one of these the subject of
an attack or boarding.
Minefield: How best to represent this in FT terms? Contact mines? X-ray
laser mines pumped by a bomb? Something else?
Stargate/Jumpgate: Could constitute 'space terrain' for navigation
purposes and also have other effects (possible gravity effects even) when
activated.
Nav buoys: Possible objective. Or useful during races as markers.
Gas giant atmospheres: Are these viable? How deep? What sort of impact would
flying through one or trying to hide in one have? They used to feature a lot
in Traveller for fuel skimming and ambushes. How reasonable is any of that?
Death Star/Giant Station: Big enough to be its own terrain, massive as a
small moon, should probably have had its own gravity?
Any others I missed?
> On Friday 08 May 2009 16:00:45 Tom B wrote:
was
> from popular usage, rather than realistic space simulation. You could
Very diffuse. What you normally see in Hubble/Spitzer images are
composites of different wavelengths portrayed as false colour. Keep in mind,
the same images often show stars in the middle of
the nebulua - they'd be 100's of lightyears inside the gas clouds,
and yet you can still see them.
I've seen it mentioned that most nebulae would actually be invisible to the
naked eye when up close. I don't know how true this is, and probably depends
on the amount of sunlight.
On very dark nights, it is possible to see the Milky Way with the naked eye,
but that's not going to affect space combat.
> Rings: Indy mentioned rings. What's a realistic estimation of ring
I believe they're very small particles, but as I said in my other email, I've
never seen good images. They might count as a 'wall'
that blocks/limits sensors.
> Planets can be done, moons can be done (though I doubt both on the
If that's my page, then Mercury is at the very limit of noticeability.
The moons of Saturn/Jupiter are smaller. However, this assumes
1"=1000km. I chose that scale to be able to fit a planet plus gravity well
onto a table where it would be the focus of the board, but not cover all of
it.
Assume a rock 3000km in diameter, made of pure iron (7.8g/cc), the
surface gravity would be about similar to Mercury. Another page on my site
(which requires Java) allows you to play with this:
http://www.glendale.org.uk/traveller/planetstats.html
Phobos (moon of Mars) has an escape velocity of 10 metres per second. An
olympic athlete can run fast enough to achieve escape velocity. That's slight
enough to be ignored by most scales in FT, though could be fun to model for a
specific engagement (where a 'ship' is something like the pods in 2001, with
very low thrust).
> Black Hole: What sorts of gravitation would you get from a black
Of course. You could have a black hole which is playable at 1km/mu!
It would just be a very small black hole :-)
If the Earth was squashed into a black hole, the gravity effects would be the
same as on my chart, as long as you stayed outside the original diameter of
the planet. Since black holing the Earth shrinks it down to only a few
kilometres, you can get a lot closer than this, so the gravity effects go up
dramatically.
You could use them to perform very sharp turns, if you survive tidal forces.
Black holes may have a large amount of matter falling into them, and a lot of
nasty radiation coming out.
> Pulsar: In SFB, a pulsar used to emanate damaging waves your shields
Pulsar's often rotate with periods measured in seconds (or less), so any arc
they sweep out will cover the entire table many times each turn.
> Sphereworld or Ringworld: Planet plus? Could make one of these the
The Smoke Ring is another weirdness.
> Minefield: How best to represent this in FT terms? Contact mines?
X-ray
> laser mines pumped by a bomb? Something else?
You'd want to mine near something important, though not sure how they'd work.
> Stargate/Jumpgate: Could constitute 'space terrain' for navigation
Very big spaceships or space stations might count. Several asteroids could
have been artificially placed in close proximity, as a base for something.
> Gas giant atmospheres: Are these viable? How deep? What sort of impact
If you look at my chart, at the surface of Jupiter, you're being
pulled 20" into the planet every turn. Saturn is a more sedate 9"/turn.
Either way, if you're hitting the atmosphere at orbital velocities it's
probably going to hurt.
> From what I've heard, the visibility in some layers of Jupiter's
B5 had at least one episode with combat inside Jupiter's atmosphere.
Not sure what a cometary tail would be like.
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Gzg-l mailing list
Gzg-l@lists.csua.berkeley.edu
http://lists.csua.berkeley.edu/mailman/listinfo/gzg-lSam said:
On very dark nights, it is possible to see the Milky Way with the naked eye,
but that's not going to affect space combat.
Tomb --> Figured so.
> Black Hole: What sorts of gravitation would you get from a black
Of course. You could have a black hole which is playable at 1km/mu!
It would just be a very small black hole :-)
Tomb --> I was meaning your typical collapsed star black hole, rather
than imploded planets or the like.
If the Earth was squashed into a black hole, the gravity effects would be the
same as on my chart, as long as you stayed outside the original diameter of
the planet. Since black holing the Earth shrinks it down to only a few
kilometres, you can get a lot closer than this, so the gravity effects go up
dramatically.
Tomb --> To? Example? Let's say I squish an Earth sized and massed Class
M planet (they're everywhere, after all). What kind of effects would I get
inside the 13" spherical region that was my former planet?
You could use them to perform very sharp turns, if you survive tidal forces.
Tomb --> There's another good question: How many gees can an FT ship
handle and what sorts of damages should excessive gravity do (and how to
implement
it)?
Black holes may have a large amount of matter falling into them, and a lot of
nasty radiation coming out.
Tomb --> Another interesting point, how to handle the radiation effects.
Pulsar's often rotate with periods measured in seconds (or less), so any arc
they sweep out will cover the entire table many times each turn.
Tomb --> Sure, but is it really a damaging radiation? Out how far? How
damaging? In SFB, I seem to recall fighting near one was a real ship grinder.
> Minefield: How best to represent this in FT terms? Contact mines?
X-ray
> laser mines pumped by a bomb? Something else?
You'd want to mine near something important, though not sure how they'd work.
Tomb --> Well, if it was a lot of small mines, you could almost mark
them as a region of the board where traverse allowed damage dice to be thrown
against the ship. Maybe speed would influence the number. If they were larger
mines, maybe they should feature on the map (but perhaps dummy
counters/mines should be used mixed in to simulate the stealth
properties of real mines).
If you look at my chart, at the surface of Jupiter, you're being
pulled 20" into the planet every turn. Saturn is a more sedate 9"/turn.
Either way, if you're hitting the atmosphere at orbital velocities it's
probably going to hurt.
Tomb --> But is that relevant directly? The atmosphere of a gas giant
extends quite far doesn't it? If so, doesn't that mean that a ship could skim
the atmosphere for fuel without exposing itself to the massive gravitation?
(Of good old MT established you needed thrust 4 or something to
land on a standard gravity world, so heavy gravity would be B-A-D news.)
And would 'hitting the atmosphere' to skim for gas (almost like entering an
orbit) be really any worse than re-entry? The space shuttle survives
that and I assume any GZG ship that can land would need to be able to. If you
hit the atmosphere at other speeds, notably off from the orbital speed, I can
see bad things happening more easily.
Tomb --> Sam mentions Comets. That's another interesting one. Would you
have a debris trail you had to fly through doing constant damage? (I'm
thinking of the armoured shuttles in Armageddon trying to get up behind the
planet
chunk...)
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Gzg-l mailing list
Gzg-l@lists.csua.berkeley.edu
http://lists.csua.berkeley.edu/mailman/listinfo/gzg-l For what it's
worth, the black holes that we can deduce the location of (we can't actually
see them) emit a lot of radiation because they're in areas of
large quantities of matter to be sucked in. A black hole the weight of
the Earth would sit very quietly in Earth orbit. There just wouldn't be enough
matter falling in to make much of a radiation risk. Similarly, a "normal"
black hole (from a collapsed sun) in interstellar space would
absorb almost no matter and would not only be non-radiating, but also
pretty hard to detect at all. The radiation depends on the matter being
"consumed", not intrinsically on the black hole itself. Unless you've got a
very good reason to fight around a black hole inside a stellar cluster, you
can probably just ignore the radiation effects.
From: gzg-l-bounces@lists.csua.berkeley.edu
[mailto:gzg-l-bounces@lists.csua.berkeley.edu] On Behalf Of Tom B
Sent: Friday, May 08, 2009 3:52 PM
To: gzg-l@scotch.csua.berkeley.edu
Subject: Re: [GZG] Space Terrain
Tomb --> There's another good question: How many gees can an FT ship
handle and what sorts of damages should excessive gravity do (and how to
implement it)?
Black holes may have a large amount of matter falling into them, and a lot of
nasty radiation coming out.
Tomb --> Another interesting point, how to handle the radiation effects.
Pulsar's often rotate with periods measured in seconds (or less), so any arc
they sweep out will cover the entire table many times each turn.
Tomb --> Sure, but is it really a damaging radiation? Out how far? How
damaging? In SFB, I seem to recall fighting near one was a real ship grinder.
> On Friday 08 May 2009 20:51:42 Tom B wrote:
Problem is, a collapsed star wouldn't be playable anywhere close to it, hence
my concentration on 'small' black holes. Neutron Stars and White Dwarfs would
have similar problems.
> If the Earth was squashed into a black hole, the gravity effects
Gravity increases/decreases according to the square of the distance.
Halve the distance, quadruple the force of gravity. Reduce the distance by a
thousand, increase gravity by a million. So, according
to my chart on: http://www.glendale.org.uk/ft/planets.html
The 4" band for Earth is measured from the surface of the Earth. That's about
~8" from the centre, and gives a gravitational pull of 6". Halve the distance
down to 4", and that quadruples to 24" pull. Down to 2" and you're at 96".
Similar for the sun, if the Sun is squashed down you work out where the new
surface is and multiply things up. The figures I've given have been averaged,
rounded and possibly fudged slightly for playability, so probably aren't good
starting points for doing this.
> Pulsar's often rotate with periods measured in seconds (or less), so
Radiation and such isn't my strong point. Probably the crew would die long
before the ship was harmed. Then again, maybe energy shields protect them.
> If you look at my chart, at the surface of Jupiter, you're being
The 'surface' of gas giants is actually the top of the atmosphere. In the real
world, atmospheres don't end neatly of course, so there will be plenty of
hydrogen above this point, just below the density that astronomers consider an
'atmosphere'.
> If so, doesn't that mean that a ship could
My figures assume 8 thrust = 1g. This is low compared to MT, but gives bigger
(more interesting) gravitational effects. With a
Traveller-like background, you might have 1 thrust = 1g, which
makes it much easier to keep away from planets.
There's all sorts of definitions of 'land' to play with. The Apollo
re-entry modules had about zero thrust, but were more than capable
of landing safely on Earth. Taking off again tends to be the tricky bit, and
requires thrust.
You don't need thrust however to not crash into the planet, just orbital
velocity. Which, for Jupiter, means you need to hit the top of the atmosphere
fast to skim up fuel.
> And would 'hitting the atmosphere' to skim for gas (almost like
If you could stay in the upper atmosphere where it's thin, then
it should be gentler then full re-entry.
Tom B wrote on 05/08/2009 10:00:45 AM:
> Any others I missed?
Extra-system, but so are nebula, are possible Oort Clouds. I believe
incredibly diffuse, but, over a sphere one third the distance to closest
neighbor system, a heck of a lot of mass. Anything recent about our own?
Evidence-inferred extra-Solar Oorts? (Sorry, having difficulty with
proper markings; apologies to the good Professor).
Indy said in a note I'm too lazy to create a 'wrote on' ref:
> Local conditions, while age-of-the-galaxy rare for a Star
See, not really, as Nemesis was exactly the model of a kind of 'local
condition' that might well concentrate bodies in a 'swarm'; a collision of a
couple of streams of bodies should be able to create a fairly dense and
chaotic area for a short time as well. Definately different from that previous
discussion, my reply to which I decided to send to draft as the dreary thread
would have just dragged on.
The_Beast
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Gzg-l mailing list
Gzg-l@lists.csua.berkeley.edu
http://lists.csua.berkeley.edu/mailman/listinfo/gzg-lOn Sat, May 9, 2009
> at 6:03 PM, Doug Evans <devans@nebraska.edu> wrote:
> Indy said in a note I'm too lazy to create a 'wrote on' ref:
You mis-attributed the above to me. You're replying to Sam Penn's reply
to
your other post. ;-)
Mk
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Gzg-l mailing list
Gzg-l@lists.csua.berkeley.edu
http://lists.csua.berkeley.edu/mailman/listinfo/gzg-lOn Fri, May 8, 2009
> at 1:21 PM, Samuel Penn <sam@glendale.org.uk> wrote:
> On Friday 08 May 2009 16:00:45 Tom B wrote:
was
> > from popular usage, rather than realistic space simulation. You
Or, as per my earlier post, toss one or two rocks onto the table and call it
good. You could justify two as being in orbit around each other. But then
they'd have to be fairly close if your MU scale is 1K km.
But that would be for a mature solar system. You might find more rocks to
contend with in a very early developing solar system.
> >
Yeah, for your general nebula, pretty diffuse. But in star-forming
nebulae, you will have localized regions of significant size where the matter
has been coalescing into stars and smaller objects to orbit said stars. Those
*might* give you terrain to pay attention to.
> > Rings: Indy mentioned rings. What's a realistic estimation of ring
I've been poking around trying to learn more about the composition of Saturn's
rings. They are thinner than I remembered from reading years back,
but fairly wide (excellent for 2-D stuff, not so good for 3-D). Saturn's
rings span from the inner D ring approximately 6,700 kilometers from Saturn's
cloud tops to the fringes of the E ring, 480,000 kilometers out. Most of the
rings are only a few tens of meters(!) thick with a total mass equivalent to a
medium sized moon. The rings themselves are made out of particles ranging from
microscopic dust to barnyard sized boulders with the
occasional few kilometer-sized object as well. Near-infrared
observations from Earth have shown that the rings are composed mostly of ice
crystals
with some impurities (i.e., rocky/dusty stuff).
> > Pulsar: In SFB, a pulsar used to emanate damaging waves your shields
Yes, pulsar periods are often measured in milliseconds. I think the slowest
spinning pulsar rotates every 8 or 9 seconds. Most are at the sub-second
level. And their beams of EM radiation are very very narrow. So narrow you
could easily move just a bit up/down from the plane it transcribes and
not be wholly bothered by it.
If you want to get an idea of how fast pulsars spin, check out this page of
pulsar sounds:
http://www.jb.man.ac.uk/~pulsar/Education/Sounds/sounds.html
> > Gas giant atmospheres: Are these viable? How deep? What sort of
> B5 had at least one episode with combat inside Jupiter's atmosphere.
I would model Jupiter's atmosphere similar to clouds on Earth. After all,
that's what they are. ;-) And no, they aren't diffuse enough to
resemble
nebulae. Nebulae are diffuse because the atoms/molecules composing them
are spread out over thousand or millions of km (or more). Jupiter's atmosphere
doesn't enjoy that kind of spatial distribution. ;-)
> Not sure what a cometary tail would be like.
Probably something a bit more diffuse than Saturn's rings, made of sand or
ice crystals. And not likely to have multi-km sized objects in it.
Mk
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Gzg-l mailing list
Gzg-l@lists.csua.berkeley.edu
http://lists.csua.berkeley.edu/mailman/listinfo/gzg-lOur resident Rock
Monkey said:
"I've been poking around trying to learn more about the composition of
Saturn's rings. They are thinner than I remembered from reading years back,
but fairly wide (excellent for 2-D stuff, not so good for 3-D). Saturn's
rings span from the inner D ring approximately 6,700 kilometers from Saturn's
cloud tops to the fringes of the E ring, 480,000 kilometers out. Most of the
rings are only a few tens of meters(!) thick with a total mass equivalent to a
medium sized moon. The rings themselves are made out of particles ranging from
microscopic dust to barnyard sized boulders with the
occasional few kilometer-sized object as well. Near-infrared
observations from Earth have shown that the rings are composed mostly of ice
crystals
with some impurities (i.e., rocky/dusty stuff)."
Tomb:
So, with 1K or 10K MUs, that's most of a board. Sounds like a representation
for them would include both a speed-related damage effect (from sailing
through the small stuff) and the occasional on board chunk big enough to be
its own sort of obstacle - from ship damaging right up to ship
destroying (depending on impact velocity).
One would obviously have to construe sensible limits of speed which of course
factors in assumptions about ship micrometeror shielding (which may or may not
relate to the ship system called shields) and hull strength as well as
composition and density of the field. A lot of that could be handwaved away by
just saying "For every full X" of speed in this region, take a beam dice at
the end of movement" or something.
You'd want to come up with a damage model for the solid chunks too, like "take
D6 damage for every X" of speed" (or something).
Obviously you'd need to mess with numbers until they made for a fun, playable
game. Then a ring battle could be pretty cool.
Questions though: How wide are rings (range of widths)? How wide (range of
widths) and how empty are the spaces between?
I ask because it would be neat to have 'bands' on your FT board - some
of which are clear (where ships wanting to take less damage can go) and some
of which are various density of rings where flying is hazardous.
Of course, in the real 3D world, your point about depth means you'd just fly
above of below them 1000 km and be just fine - safe and sound. No one
would
ever really fight in that thin 100m or less plane of the rings - it
would just be pointlessly masochistic.
But that's the great thing about an FT game - it has to be fun, not
scientifically accurate.
TomB
D'oh!
Indy wrote on 05/10/2009 05:28:49 AM:
> You mis-attributed the above to me. You're replying to Sam Penn's