OK, I've mumbled some things about this in the past and now I'm starting to
think about this in more detail now that I've got a few things taken care of.
I have in the past, begun to think about an extension to Full thrust that
allows for a better scale of scenario build up rather than the
basic X-thousand points and a table kind of matches.
The basic concept is that the table top that we normally play with is a very
small fraction of the total space around a system. This total space is likely
to be subdivided off with hexes for ease of diagonal movement. Its not super
accurate, but its a good balance between a grid and free angles and distances.
At the center of your 'map' is your system core at about an Astronomical Unit
(Distance from Earth to Sun). Each hex is about.5 AU's
The thing I'm stumped on is exactly how to represent movement based upon a
task force's (and specifically the ships comprising said task force) movement
across individual hexes. I want the scale of acceleration between each ship to
be represented nicely but not too quickly.
Does 1 hex per Thrust point per turn seem correct? It'd make it easy to work
up movement velocities but I don't want a task force that is at an obscene
speed to come to a halt in one hex. They should spend
several turns after a turn around retro-thrusting to slow down.
Once two groups of ships meet in the same hex, they get moved to the play
table and there you perform the quick battle. This could allow for some really
interesting actions between a scout trying to get close to perform close ID's
of ships and not getting whacked by the taskforce... It could also allow for
groups that have a slight edge on velocity overtaking a group that is slightly
slower and running them down.
Basic principles are:
1 Hex =.5 AUs and a nebulous area of one ship scale (std FT scales or Ship
Action Scale) map.
80-100 hexes across is the overall map known as Theatre Action Scale
At the edge of the Theatre map is the hyper limit for safe FTL
transition. FTL transition near the Primary or other major/minor
planets will have varying degrees of hazard. FTL into the system is
only on the edge, closer in results in ship/task force loss.
Transition further out results in longer times to enter the system and is
reserved for special scenarios as it takes a week or more to FTL that far out
and thrust in at low speed to avoid detection.
Any asteroid belts will have a maximum safe speed for transition across, this
is represented either by picking your way through safely or by using thrust to
go around in the 3rd dimension (abstracted just like in Ship action scale).
Ships that do not FTL, thrust, maneuver, fire energy weapons or emit
ECM/Sensors will not be placed on the Theatre map.
Ships that have FTL'ed, thrust-ed, maneuvered, fired energy weapons
or emitted EMF energy will be represented as a task force icon/model.
Highest thrust burn used by the task force and varying degrees of information
based on weapons fire and or sensor use will refine the information available
about that particular task force. Data available would be kind of sensors,
total mass and thrust, type of weapons fire, etc.
Taskforces will be those ships in a specific hex. They could be a
full battle line, a convoy of cargo vessels, a small CA/DD task
force, ships (CLs/DDs/FFLs) on picket duty, a Scout(s), or a
anti-scouting DD screen.
Range for sensors is still being refined but I'm leaning towards a concept
where higher grade sensors under the current model allow for broad sweep scans
of areas or quadrants for detecting silent running vessels. A question is
levels of stealth...
Fighter groups will be detectable at closer or further ranges depending on
what really feels right. They will be detected at much
closer ranges compared to ships (Active and passive). Probably 1-2 AU
on passive, 6-8 AU on active
I arrived at this scale as a balance between realism and playability.
Too fine a scale and you've got an im-measureably huge map with
thousands of hexes. Too course and the tactical flexibility isn't quite real
enough. Distant Binary systems would be represented by two big maps, close
binary stars aren't likely to be sites of any large population center other
than a temporary military, corporate or scientific post.
The combination of sensor effectiveness and range will make the need for
sensor pickets and scouting extremely important in the game. It will also
allow for varied developments of carriers being separated from gun type groups
and still contributing to the fight in a
realistic manner very important. Hunt the carrier/assault group
scenarios would be very playable and very fun. The use of bogeys and weasel
boats will up the ante quite nicely too.
Keep in mind, I'm still batting the concepts around but the basic idea seems
solid and playable. Thoughts comments?
> The thing I'm stumped on is exactly how to represent movement based
Vector on a hex grid is easy.
> 80-100 hexes across is the overall map known as Theatre Action Scale
That's a LOT of hexes, don't you think?
> Any asteroid belts will have a maximum safe speed for transition
Well, as long as you don't outrun your radar, you should be safe. I wouldn't
bother with this.
> Keep in mind, I'm still batting the concepts around but the basic
> At 6:44 PM -0400 8/6/01, Laserlight wrote:
Pretty much why I'm going that direction...
> > 80-100 hexes across is the overall map known as Theatre Action Scale
It may get scaled down, but some of the size is due to the need for the
correct scale representing an entire system. Generally you're going to be
fighting near planets or on the axis between an attacker and the planets you
are defending. So there will be a lot of empty space that you don't fight in.
But, remember, that 100 across is diameter, its half that from edge to center.
If its too small then the entire inside area of the Solar System (the
benchmark) is going to be in one hex area. Thats too small. The earth is at 1
Astronomical Unit (143 x10^6 miles), Venus.72 AU Mercury.4 AU Mars 1.5 AU
Jupiter 5 AU Saturn 9.5 AU Uranus 19 AU Neptune 30 AU Pluto 39 AU
If a map is based on.5 AU per hex then from center to Uranus will be 38 hexes
out with a diameter of 76 across. Neptune will be 60 hexes out and 120 hexes
across.
I'm willing to dump Neptune and Pluto as they're just too far out from the
sun. Pluto is way out there and on a rather odd orbit. They're pretty much
backwaters, but the closer Gas Giants will be especially important with their
large size, high proportion of moons and large volume of Hydrogen and Helium
for mining and power generation (Fusion is the likely power source right?).
> > Any asteroid belts will have a maximum safe speed for transition
Some of the idea is to keep units from ignoring it entirely. Its not
insubstantial and is actually quite a significant size considering. It also
makes for more possibilities of that belt being some sort of barrier in a way.
> > Keep in mind, I'm still batting the concepts around but the basic
What? Good that I'm still working the ideas out or good the ideas in
general... :)
> OK, I've mumbled some things about this in the past and now I'm
Nothing wrong with that!
> I have in the past, begun to think about an extension to Full thrust
Obligatory statement of desire for an "official" campaign system based on
"Canon"
> The basic concept is that the table top that we normally play with is
Looking at the other posts on the subject, and after some thought I think that
this would in fact work OK. An alternative is to merely work on a range band
concept similar to Traveller and abstract it out majorly. This way is probably
somewhat easier and more fun...
> The thing I'm stumped on is exactly how to represent movement based
All sounds OK.
> Basic principles are:
Ok.
> At the edge of the Theatre map is the hyper limit for safe FTL
As an old Trav. player I don't like this. I like the Planetary Diameters
better. For FT I would be more tempted to place this as a series of concentric
rings around any planetary hex...
> Any asteroid belts will have a maximum safe speed for transition
Have to think about this one...
> Ships that do not FTL, thrust, maneuver, fire energy weapons or emit
Sure, makes sense.
> Taskforces will be those ships in a specific hex. They could be a
You may want to give some thought to C&C ala SFB...
> Range for sensors is still being refined but I'm leaning towards a
Yup, but with the current rules I would just argue for running hot or cold
basically, and the amount of fire controls active, etc...
> Fighter groups will be detectable at closer or further ranges
Seems a bit high to me... But who knows. This also begs the question of what
exactly "fighter endurance" means in a strategic game. I would argue that you
don't operate fighters on that scale.
> The combination of sensor effectiveness and range will make the need
All very true, plus MT missile bombardment or even another variant class of
SML missiles.
> Keep in mind, I'm still batting the concepts around but the basic
First looks are good.
> >That's a LOT of hexes, don't you think?
> Venus .72 AU
So make Saturn the "edge", 20 hex radius.
> > > Any asteroid belts will have a maximum safe speed for transition
I
> >wouldn't bother with this.
Lots and lots and lots of vacuum, not much rock. And if you do find yourself
approaching a rock, it shouldn't take much of a burn to avoid it. I'd ignore
it. Unless the natives put sensors or bases there.
> What? Good that I'm still working the ideas out or good the ideas in
> ------------ Original Message -----------
And you can probbaly ignore Mercury with impunity (although launch
lasers emplaced there were used in the First Man-Kzin War).
> > > > Any asteroid belts will have a maximum safe speed for transition
Asteroids would be a great place for a minefield or an ambush. I
wouldn't take an attacker force through an asteroid belt - I'd detour
through the Z-axis. You might incurr a small movement penalty, you're
more likely to see a noticeable delay here than in an unopposed transit.
> On Mon, 6 Aug 2001, Ryan Gill wrote:
> At 6:44 PM -0400 8/6/01, Laserlight wrote:
> > > Any asteroid belts will have a maximum safe speed for transition
The asteroid field in our solar system can be represented by....let's see,
take a large room (something on the order of 15'x15' or so) and toss in a few
marbles. This would represent a more or less crowded area of our asteroid belt
(where 'belt' is a misnomer, really). Some years ago I wrote up a study on
asteroid fields for gaming purposes. The summary was: take a small rock, toss
it on the table, and voila`. You're in the asteroid field. I can repost this
if there is interest,
or send it to you off-list. It could even be buried somewhere deep in
the FT archives (not sure if Jerry's archives go back that far or not).
> At 8:03 PM -0400 8/6/01, Laserlight wrote:
By excluding Uranus you drop 15 possibly habitable moons from the equation.
> Lots and lots and lots of vacuum, not much rock. And if you do find
Where do you get your easily obtained isotopes, metals, silicates and carbon
chains for industry? Well, I'd think asteroids would be bloody great places
for that. Lots of intra system commerce between there and the factories around
the Near Gas Giants and inner planets.
> > What? Good that I'm still working the ideas out or good the ideas in
Comments noted... Thanks btw
> At 11:43 6/08/01 -0400, you wrote:
> I can repost this if there is interest,
I'd be interested in seeing this, thanks.
> >So make Saturn the "edge", 20 hex radius.
So? By excluding the Oort cloud you drop quazillions of cubic kilometers of
this and that off the table. I still think 100 hexes across is too much.
> >Lots and lots and lots of vacuum, not much rock. And if you do
Yep. Just that it's not really dense enough that you should have to worry
about driving through it.
> At 7:02 PM -0500 8/6/01, David Rodemaker wrote:
I'm working it as Canon as possible, but I think you're talking to Jon. Let me
point out that you have campaigns that could be set up where you're fighting
for control of a system and then there are campaigns where you are fighting
for control of many systems. Each has a different focus and a different set of
parameters involved, as well as time scale. I'm going for the first kind which
means, there isn't resources like raw materials and ships being built to keep
track of.
> Looking at the other posts on the subject, and after some thought I
Lots of thinking that works on a broad area, but can affect small details.
like, where do you send your scouts. Which vessels go active with sensors,
etc.
[snip]
> > At the edge of the Theatre map is the hyper limit for safe FTL
The problem with the planetary diameters function is that you will never ever
have a system that is defensible. Its going to be outposts that are separated
and always easily isolated from each other. Making a perimeter that allows
scramble creates a frontier of sorts that is more easily watched. Some of the
concepts seem to work thematically as I've worked a bit of Honor Harrington
into the concepts. I hope Jon doesn't mind...
It also makes for more fights that involve the raiding force coming down the
slot. ITs not as much fun if you can 'pop' in and hose the ship yard then pop
out before the ships on station the next planet over can get to it.
[snip]
> > Taskforces will be those ships in a specific hex. They could be a
Well, the overall com signals are whisker thin lasers. I'm shying away from
the gravitic pulse comms stuff for now. (perhaps the Grav Drive Aliens would
use it?) This isn't a big deal as it only takes 7 seconds for light to travel
1 AU...or something like that. So at the extreme range of the edge of the
system you're talking about something like 16 minutes max.
> Yup, but with the current rules I would just argue for running hot or
I want the ability to differentiate between vessels at range. A bit more
precision...at least as an option...
> > Fighter groups will be detectable at closer or further ranges
I'm thinking that CEFs would be burned to cover 1 Hex extra/turn or
to change course. This would give a good approximation of their endurance and
if combat were to take place, they'd be in a world of hurt. They'd eventually
get back if they used all their CEFs but it'd be only if the SAR teams went
out and towed them back.
1 Free CEF for initial vector and direction (ship's catapults) Move 1 Hex per
turn Cost 1 CEF to change direction. Cost 1 CEF to increase movement to 2
hexes per turn. CEFs in the hex (Ship Action Scale) are burned normally.
So a mission could have a fighter group running out at 2 CEF/ turn (1
CEF burned) for 4 turns (8 Hexes away) Making a course change to adjust to the
latest target data (2 CEF's burned now). Fighting for two turns (Burning 3
CEFs in the process now 5 CEFs burned total) then returning at low speed to
the carrier.
Obviously Fast Fighters would move 2 hexes per turn and LR would have their
normal 9 CEFs.
You could then in this process have fighters out there where you don't as the
other guy expect them and have them jumping your task force unexpectedly.
> > The combination of sensor effectiveness and range will make the need
I'm thinking a uber LR MT missile...but that is additional. I need to get the
overall theatre tactics down before the new weapons pop up.
> > Keep in mind, I'm still batting the concepts around but the basic
Good...Its been banging around in my head for a while...
> At 11:43 PM -0400 8/6/01, Mark 'Indy' Kochte wrote:
Granted space is big. But what is the granularity here? NASA has fits every
time they send something through the field. Some smaller chunks that are hard
to map are always the bigger worry. Even still, closer
to earth we're still finding damnably big rocks (3-6 Mile Pluse size)
really close.
Going through really dam fast (6 hexes per turn) would put you through the
belt fairly fast and make it really hard to avoid a rock that you didn't
track. If you are going through with passive sensors only, how are you going
to see that rock before it smacks your Flagship in the bridge? Especially if
its also mined unexpectedly...
> It also makes for more fights that involve the raiding force coming
Well, it's a lot more fun if you are the popper, not much fun at all if you at
the poppee. Doesn't make a good battle, I agree.
> Well, the overall com signals are whisker thin lasers.
Kinda tough to pull over over multiple AU.
> away from the gravitic pulse comms stuff for now. (perhaps the Grav
> At 12:08 7/08/01 -0400, you wrote:
Yep, space IS big currently my operational level rules really only deal
with areas like the earth-moon system, the scale of the solar system can
be pretty daunting, but keep at it Ryan:)
On Tuesday, August 07, 2001 2:10 PM, Ryan Gill
[SMTP:rmgill@mindspring.com]
wrote:
> Well, the overall com signals are whisker thin lasers. I'm shying
It's more like 8 1/2 light *minutes* to travel 1 AU (Indy could give you
the exact figure). So comm time will be closer to 6 hours; if you can hit your
target with the comm laser.
'Neath Southern Skies - http://home.pacific.net.au/~southernskies/
[sstrike] Raider Fleet of War Leader Kel'em'all
> At 12:08 AM -0400 8/7/01, Laserlight wrote:
the extra off the side if a 30 hex radius "system" gives the edge where the
FTL limit is and makes for an area where you can work it as
a no-mans-space...
> Yep. Just that it's not really dense enough that you should have to
Possibly...but having some sort of un-sure shoals to slow down a bit
in, is important....
> At 12:17 AM -0400 8/7/01, Laserlight wrote:
It'd get boring pretty quick...
> > Well, the overall com signals are whisker thin lasers.
Possible...the C&C issue will be something to think on....hard to model in a
game though. Unless you put each task force in a certain area under the
control of a particular player who can't talk to the other players on his
side...
> > away from the gravitic pulse comms stuff for now. (perhaps the Grav
Ack you're right. Its a 7 minute transition from the Sun isn't it? Hmm,
perhaps vibrating singularities is the way to go. How do the
ships that FTL get detected? A major pulse in T-K range Grav waves?
> > > Well, the overall com signals are whisker thin lasers.
I meant the "whisker thin" part--it gets "house-thin" pretty quick.
> >Right around 500 seconds IIRC
That would be 8m20s, assuming my round figure of 500 is right.
> Hmm, perhaps vibrating singularities is the way to go. How do the
> the extra off the side if a 30 hex radius "system" gives the edge
If you have Harrington in mind I think you'll find their jump limit
> At 12:42 AM -0400 8/7/01, Laserlight wrote:
Hmm, More than Honor has the Hyper Limit based on the spectral class of the
star. The Sun is a G2 Dwarf (Main Sequence) and has a Hyperlimit at 21.12
light minutes. I'm not sure why David bases it on spectral type and not mass
as he has the hyper limit for a red giant as 5.64 LM. I'm inclined to put it
out further past the first or second Gas Giants in the case of Sol.
> >If you have Harrington in mind I think you'll find their jump limit
2.5AU, then.
> I'm not sure why David bases it on
I haven't seen that one. Is that inside the star? Might he be thinking of the
amount of energy rather than mass?
> I'm inclined to put it out further past the first or
I'm inclined to agree, but not all that far past Saturn. If someone wants to
go attack Triton, set it up as a special scenario.
Has anyone tried to use something akin to the Alderson Drive used in "A Mote
in Gods Eye"? I am wanting to do something along those lines for my FTL but
also have the option of jumping from a planetary Alderson point.
opinions?
Responding to a couple of posts here:
> >Obligatory statement of desire for an "official" campaign system
No argument there, and yes, I *was* talking to Jon... <g>
> > > At the edge of the Theatre map is the hyper limit for safe FTL
And Laserlight:
> Unfortunately this screws up your system scale if you do it and means
I guess that I just don't see this. What it does mean is that your actions
*could* take place closer to planets, but I don't see this as a given. First
we have jump distance set by distance within the originating gravity well
(this isn't defined as either solar or planetary, but I suspect would probably
be both...)
Since you are also trying to work it as Canon as possible I don't feel bad
about quoting "The Book", even if does make me feel like an SFB/GW
geek...
<g>
FB1 states that "for precise military operations, therefore, it is normal
practice for the fleet to reassemble-" (after the normal series of jumps
to
even get there) "-well out of the target system and then proceed in
system in a succession of much shorter than normal jumps in order to maintain
some semblance of cohesive formation."
There are also statements in FT about not jumping into gravity wells as it is
too deep so there is also evidently some issues with jumping *into* the well
in addition to jumping from within one.
"The final approach, under Normal Space propulsion, can then take anything
from a few hours to several days depending on the accuracy of the last jump in
system and how fine the jump navigator dares to cut the gravitational limit."
In addition, there is an absolute minimum of a six hour turn-around time
between jumps, that being with "military drives and power plants, along with
the most sophisticated jump navigation software and tremendous crew stamina,
even with chemical assistance. On average, naval vessels on most missions will
make no more than one jump per day."
There is also the implication that you don't jump right into combat because
for about a hour afterwards (or at least 20 minutes) the crew involved in the
Jump is good for nothing, and certainly not for combat...
All of this implies that the outer edge of the gravity well is at the outer
edge of any system (several *days*??), but that you can cut it a great deal
tighter (several hours...) It almost sounds like for military ops that the
> From Ryan's original post
> Some of the idea is to keep units from ignoring it entirely. Its not
It's really not going to be, though. If you want genre SF,its fine to have a
dense asteroid field, but if you're going for 'realism', a field like ours is
utterly ignorable as a nav hazard.
> Where do you get your easily obtained isotopes, metals, silicates and
In that case individual asteroids could be the targets of fleet actions. But
you'd never have more than one (or a binary pair (much) less than 1 MU across)
on a FT tactical map during any single battle.
> Granted space is big. But what is the granularity here? NASA has fits
The reason NASA has fits going through the field is _not_ because of the
hazard, but because its so hard to pass _close_ enough by an asteroid to
get bonus science on the way to your final objective. The Mathilde flyby for
NEAR and the Ida and Gaspra flybys for Galileo took a heck of alot of
planningn to make happen at all.
As for FTL limits, I like the Idea of a System limit based on stellar mass
with commensurately smaller planetary limits. Scott field did a PBeM where the
planetary hyperlimit was a tactical consideration. He set the system's
"Hyperwall" - controlled by Starmass, if I recal, at a little over 1 AU.
An Earthlike planet's hyperlimit wason the order of 200 MU.
For Ryan's game scale, I'd up both of them. Make a Sol-type star's
hyperwall say 5 AU or 10 hexes. Make jupiter and saturn's hyperlimits 2 hexes
and
Neptue/Uranus 1 hex to keep the strategic scale rather than tactical.
(that's a pretty steep exponent even so, given the sunis on the order of 1000
times Jupiter's mass. it measn that bases on outlying planets and moons are
more exposed than system cores, as well they should be.
Or you could base hyperlimits or hyperwalls on some completely different
High-SF quality. For example, go whacked out and say the total biomass
on a planet determines the hyperlimit (Earth's would be say 5 or 10 AU). Or
you gould say that the FTL limit is subject to hyperspace "tides" that sweep
in and out of the system based on some PSB mechanic. That could mean that on
rare occasions, even core worlds could be subject to direct assault, and
defensive fleet movements would have to take the tides into account.
> On Tue, 7 Aug 2001, Ryan Gill wrote:
> At 11:43 PM -0400 8/6/01, Mark 'Indy' Kochte wrote:
[asteroid navigation stuff]
> Going through really dam fast (6 hexes per turn) would put you
You won't. And it's very likely that space craft, travelling at *any* decent
velocity, are going to have some kind of active sensors up in order to avoid
terrain in space, even if the active sensors are at
low-level (there'll come a point where any emmissions will be
indetectable from background energies). Thus Laserlight's comment about not
flying
faster than your radar. ;-)
Mk
> > Hmm, More than Honor has the Hyper Limit based on the spectral class
Let me de-lurk long enough to say that the Sun will become a red giant
once
its hydrogen supply is essentially exhausted -- and that red giant won't
mysteriously suddenly get more massive. As for the radius, figures vary but
most likely the Earth and maybe Mars would be "swallowed" by the expanding
solar surface. Perhaps the 5.64 LM figure is distance from the surface, and
not center?
A note on spectral type and mass: G2 is spectral type, dwarf/Main
Sequence (V) in combination with G2 gives you the mass, so saying G2 V gives
you both... Admittedly, "red giant" is a somewhat nebulous (!) term and could
imply something more massive than what the Sun will become (but not much
more!).
Maybe one solar mass concentrated into a G2 V star warps spacetime much more
"steeply" than that same solar mass distributed over the larger volume of a
red giant, making an FTL jump more difficult close to the G2V than it is close
to the red giant...?
> On Tue, 7 Aug 2001, Robertson, Brendan wrote:
> On Tuesday, August 07, 2001 2:10 PM, Ryan Gill
> > seconds for light to travel 1 AU...or something like that. So at the
> > extreme range of the edge of the system you're talking about
8-1/2 minutes is a good number to work with for this. But if you want
the exact figure, it's more like 8.317 minutes to the AU at light speed.
If someone wants to do the math themselves:
1 AU = 1.4959789x10**13 cm
c (speed of light) = 2.99792456x10**10 cm/s
Neptune's orbit is accepted to be ~30.07 AU out; Uranus 19.18 AU. I'll leave
it as an exercise for the reader to figure out how long
light takes to travel these distances. :-)
Where do you want the 'edge' of the solar system to be?
> At 7:51 AM -0400 8/7/01, Laserlight wrote:
yep.
> I haven't seen that one. Is that inside the star? Might he be
I certainly think its inside, if you count the center of mass. It may be from
the surface of the star, still awfully close....its inside Venus' orbit for
sure if its Center of Mass.
Its in the back of More than Honor. I think basing on spectral class and not
mass of the star is a bit of a problem. I think Spectral class is partly
related to mass, but all stars go through a red giant phase when they've
burned down the H and HE content.
> At 9:23 AM -0400 8/7/01, Izenberg, Noam wrote:
In some cases they should work out like islands in the WWII pacific campaign.
Ideal locations for orbital fortresses where fighters and
other non-ftl craft are based. It'd give you a more balanced
disposition around the system when certain major planets are in concordance or
in a major conjunction.
> The reason NASA has fits going through the field is _not_ because of
Granted.
> As for FTL limits, I like the Idea of a System limit based on stellar
Related to Mass seems to make sense in the Physics aren a. The distance per
unit mass is the question. Planets like Jupiter would have something as well
pushing that boundary out too.
> For Ryan's game scale, I'd up both of them. Make a Sol-type star's
That would make Close Binary Systems have no hyper limit what so
ever....
> At 9:25 AM -0400 8/7/01, Mark 'Indy' Kochte wrote:
Welll...I don't know about any active sensors...especially if there is a
chance they have that perimeter setup as a first defensive line. Sounds like a
really good place to loose the element of surprise....still many of these
tactical dynamics will let them selves be known in the game on their own...
> At 9:25 AM -0400 8/7/01, Jerry Acord wrote:
I always understood that Earth was going to be uncomfortably close to the
surface and that Venus was going to get baked to a cinder. Mercury would end
up inside.
> A note on spectral type and mass: G2 is spectral type, dwarf/Main
Red Giant, Red Super Giant? which ever I guess. I think that Weber
was being a bit nebulous. He does have that semi-automatic lever
action in March Upcountry...
> Maybe one solar mass concentrated into a G2 V star warps spacetime much
But does the orbital ummmmm retention (?) stay the same? ie do the planets
orbits alter at all? If not then the gravity well doesn't change.
> At 10:00 AM August 07, 2001 "Ryan Gill" <rmgill@mindspring.com> wrote:
> I always understood that Earth was going to be uncomfortably close to
My recollection is that the size of the Sun's red giant phase will probably
engulf the Earth. But as we always said in grad school, what's a factor of 2
between friends? Especially in astronomy...
> But does the orbital ummmmm retention (?) stay the same? ie do the
Consider two scenarios: 1) the Earth orbiting the Sun at 1 AU; 2) the Earth
orbiting a 1-solar mass black hole at 1 AU. The orbit is the same in
both scenarios. Replacing the Sun with a b.h. will not magically suck all the
planets into it. 1 solar mass is 1 solar mass. However, close in you
_will_ get weird effects and spacetime _is_ warped much more severely
close to the b.h. than it is near the Sun. It's just further out that the
severe warping smooths out. That's why a b.h. will have an event horizon, but
the Sun obviously doesn't...
(SImilar argument, but in the opposite direction, for G2V vs. red giant)
So as far as FTL / hyperspace travel is concerned, you could say the
"higher order spacetime perturbations" of the denser object lead to a
relatively
further stand-off distance for safe hyperspace entry etc. etc. etc.
(hands waving vigorously...)
Cheers,
> At 10:16 AM -0400 8/7/01, Jerry Acord wrote:
> Consider two scenarios: 1) the Earth orbiting the Sun at 1 AU; 2) the
Course getting the Sun to become a black hole when it isn't over the
Chandrakar (sp?) limit is of course impossible. Thats the nice thing about a
main sequence dwarf.
> _will_ get weird effects and spacetime _is_ warped much more severely
Ok, I see, the slope is sooner for the gravity well in the case of the larger
star. But is the well as deep since it's spread out?
> (SImilar argument, but in the opposite direction, for G2V vs. red
(hands
> waving vigorously...)
Yeah, it'd be easier in my mind to base it off of total mass of the
star/system. The safe region of a Moderate to distant binary system
(or even a trinary with a 2 dwarfs and a compact main sequence) would be
nasty.
> At 8:00 AM -0500 8/7/01, David Rodemaker wrote:
> I guess that I just don't see this. What it does mean is that your
First
> we have jump distance set by distance within the originating gravity
[snip all the game based and very nice canon FTL stuff]
> There is also the implication that you don't jump right into combat
This is something people like to forget....especially someone in our local
group that wanted to jump into combat as a cheese factor. He wasn't happy with
the mention of zero weapon effectiveness for a turn. He was also quite upset
at the idea of not having shields up. "see look at the book, it says desperate
tactic!" We let him have his shields but he sucked it up for a turn when
everyone got to shoot at him without retribution.
> All of this implies that the outer edge of the gravity well is at the
I'm understanding it to be that you jump into the region way beyond the Oort
cloud and assemble your strike force. It is such a massive volume of space
that unless the Red Force has awful operational security, then they aren't
going to worry about getting bushwhacked. Once all the ships or the appointed
time has come, the ships will jump in over the shorter jumps to the edge of
the solar system in groups. Some final stage here (I'm bidding for the last
FTL transition) is where the system defenders (Blue) get early warning of the
large number of ships not scheduled for entry
So, Blue knows there are some ships out there, Red is seeing some energy
signatures in system some are obviously sensor pickets due to broad range
comms traffic (messages to merchant and civil ships to find safe harbour, news
leaks, etc), some are obviously merchants, some are unknown, and there are
likely a number of ships under EmCon that he can't see. Blue however see's
signatures for the task force and once the picket's get closer, they'll be
able to get a better idea of what has shown up to make their day bad.
> On Aug 7 , "Izenberg, Noam" <Noam.Izenberg@jhuapl.edu> wrote:
The NASA thing has been covered adequately by others, so I'll touch briefly on
the "big rocks near Earth" question. The biggest reason that they don't tend
to be found is that we're not looking for
them. A few (less than 10) telescopes, even Earth-based, actively
looking for near-Earth asteroids, would find any that habitually stay
near the Earth fairly quickly. There just isn't the funding available to do
that right now (meaning that governments don't WANT to spend the money there,
rather than that they don't have enough to do so if they did want to) (I'm not
going to touch on why, and whether this is justified, my point is merely that
it is well within our capability to find these things if we really wanted to).
Of course, most asteroids that approach close to the Earth also get fairly far
away, and may have long orbits (some may even have
orbits looking quite a bit like short-period comets). For these, you
not only have to detect them (which can be done) but figure out their
orbits (which would be more difficult). Of course, space-based
telescopes would make all of this much easier.... The thing right now is that
you tend to find asteroids while looking for something else,
because there really isn't any funding to look for near-Earth
asteroids (as an independent activity).
> Or you could base hyperlimits or hyperwalls on some completely
One mechanism that I haven't seen used very often which might be worth looking
at is magnetic flux. It has several advantages:
-most planets have a fairly high field, but not all. This means
that some planets might be naturally exposed, while others (even others
farther out) are better protected.
-magnetic fields follow an inverse cube law (for dipoles,
anyway). This means that there will be less difference in field limits from
smaller to larger fields (in general).
-jovian-style gas giants put out a fairly intensive flux. Useful
for shielding their moons (so do stars, and so would almost any habitable
planet).
-Screens use (PSB) magnetic fields to deflect particle beams. If
that is the case, you might have to drop your screens just before you jump.
Maybe even a LOT before....
I always thought that the jump might produce a taychon pulse, detectable
from in-system. Useful for campaigns, but just PSB.
Looking at the the rules for FTL drift and the description of jump in FB1, it
appears that there are some forces at work that make jumping difficult to
calculate (aether currents,
slow passage of the dimentions over each other, butterfly-
effect, etc.). If you assume the jump drift described in FT2 is for the final
(relativly short) jump, it could be possible
that the jump-drift multiplies (maybe even expodentially)
with distance jumped.
So that a 1au jump may generate drift of 1-36mu. A 10au jump
may produce a 10-360mu or 1-36^10mu drift. So jumping from
star to star might give a jump drift in au.
The Fluff on p44 of FB1 indicates that the deeper in a gravity well a ship is,
the shorter distance it can jump. I assume that this also applies if the jump
exit is further in the gravity well.
It sounds as if a ship will take several jumps (4+?) out of
a system, jump interstellar distance, and then take several jumps back in to a
system to get back down the gravity well.
---
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, Ryan M Gill wrote:
> At 10:16 AM -0400 8/7/01, Jerry Acord wrote:
Chandrasekhar Limit, which is 1.4 M(solar). My info is a little out of date
(it's been a LONG time since I seriously studied black holes, and
really most recently only galactic-sized super-massive BHs), but I think
there was theoretical evidence that you could have a black hole of 1 solar
Mass.
In any event, what Jerry was trying to illustrate is simply that the mass
should be irrelevant when looking at the overall gravity well effects. You
could look at all masses as point-sources for this exercise, too.
> >_will_ get weird effects and spacetime _is_ warped much more severely
Be careful your adjective "larger". Do you mean more volume or more mass?
It does play a difference. ;-)
IIRC (without having all my texts onhand and no time to spend going up to the
library to do this research) the volume of the source plays a role in how wide
the gravity well is, but the depth should be essentially the same for the same
mass.
> >(SImilar argument, but in the opposite direction, for G2V vs. red
(hands
> >waving vigorously...)
Don't hurt your head on this stuff. Find a good PSB solution. :-)
Mk
In message <p05100e01b795c4b730c5@[157.166.130.123]>
> Ryan M Gill <rmgill@mindspring.com> wrote:
> At 10:16 AM -0400 8/7/01, Jerry Acord wrote:
Not impossible, just very difficult, and I shouldn't happen naturally
:-)
Anything can be made into a black hole if you squeeze it hard enough -
however, small ones don't last very long ;-)
> >_will_ get weird effects and spacetime _is_ warped much more severely
(hands
> >waving vigorously...)
Wandering off at a slight tangent, an old friend of mine proposed a fictional
hyperdrive where the safe 'jump' points were at the Lagrange points
(specifically the L4 & L5 ones) of a planet's (or moon's) orbit.
So, they'd be close in, but in a predictable position.
> It sounds as if a ship will take several jumps (4+?) out of
IIRC it actually sounds like there are a number of jumps for stellar travel.
The high, high end distance wasn't that much...
> On Aug 7 , Ryan Gill <rmgill@mindspring.com> wrote:
Unlikely. After all, if you're using constant acceleration with a reaction
drive, your drive is putting out WAY more energy than any sensors you could
ever hope to employ. A fusion torch in the asteroid belt might easily be
visible to the naked eye from Earth, and even if you're not THAT over the top,
if you're thrusting you pretty much can't hide. And if you're not, don't
bother with the scan because if you're not thrusting you can't dodge.
This might even suggest that ships would use the biggest radar-
equivalent they could for scans -- after all, a bit more radiant
energy won't make that much difference. Alternately, if you're decelerating on
your way through the belt (which any invaders may
well be), you might not have to worry much about rocks -- anything
that will survive your drive plume may be trivially easy to dodge (and
reflected light will be GREAT for detecting asteroids too).
> At 1:37 PM -0400 8/7/01, Bell, Brian K (Contractor) wrote:
Makes sense.
> So that a 1au jump may generate drift of 1-36mu. A 10au jump
Aye, sounds like a reason for *gasp* a table!
> The Fluff on p44 of FB1 indicates that the deeper in a gravity
I tend to think that the jumps from systems to another system will be like
golf from one side of course to the other as opposed to just towards the next
hole (a next system jump which would be easier and shorter). You tee off from
the edge of the system and then as you get closer to the hole (target System)
you are headed towards, you
shorten up your leaps/strokes and have smaller error rates.
> Unlikely. After all, if
that's a big "if", with not much fuel tankage on the SSDs to support it.
> you're using constant acceleration with
> At 1:42 PM -0400 8/7/01, Mark 'Indy' Kochte wrote:
It was my understanding that if you were under the 1.4 then a dwarf
was the result after H-Fe supply burn out and after nova.
> In any event, what Jerry was trying to illustrate is simply that the
You
> could look at all masses as point-sources for this exercise, too.
Aye, the question is the slope of the gravity well affecting the FTL limit. I
guess a way of putting it is what "angle" of gravity well slope is a safe FTL
transition happy with?
> Be careful your adjective "larger". Do you mean more volume or more
When I say larger, I mean mass. All stars get bigger and smaller physically
over their lives. Thats why I was questioning the sole use of Spectral Class
by weber for determination of the Hyper limit.
> IIRC (without having all my texts onhand and no time to spend going up
a more gradual slope vs a really steep slope in other words (giant vs midlife)
> Don't hurt your head on this stuff. Find a good PSB solution. :-)
Likely I'll find a nice table of star masses and figure an easy relationship.
I'm still working on the other stuff before I worry about some of the
constants. I figure most systems with any reasonable habitation won't have
Giants or close binary's since they tend to be unhealthy for life in general.
Nice G class V's are likely the norm for where humans live....
On Tue, 7 August, 2001 1:42 PM Mark 'Indy' Kochte wrote
> On Tue, 7 Aug 2001, Ryan M Gill wrote:
The Chandrasekhar limit is the mass above which electron degeneracy pressure
will not balance gravitational forces in a white dwarf (leading to collapse
into a neutron star, in which neutron degeneracy pressure is the
"counter-agent" to gravity).
Beyond about 2 Msolar, neutron deg. pres. is not enough to balance
gravitational forces and you'll have a black hole.
So if a big main sequence star (say, 20 Msolar) goes "kablooey" (technical
term) when it exhausts its nuclear fuel, and the central remnant is over 2
solar masses, you'll get a black hole.
http://archive.ncsa.uiuc.edu/Cyberia/NumRel/BlackHoles.html
Lots of info about black holes, spacetime wrinkles & stuff like that.
> In any event, what Jerry was trying to illustrate is simply that the
You
> could look at all masses as point-sources for this exercise, too.
Yup. Except when it comes to getting really close to very dense objects.
> > Ok, I see, the slope is sooner for the gravity well in the case of
What matters really is _density_. Lots of stuff in a small volume.
> Don't hurt your head on this stuff. Find a good PSB solution. :-)
Amen!
Cheers,
> On Tue, 7 Aug 2001, Ryan M Gill wrote:
> At 1:42 PM -0400 8/7/01, Mark 'Indy' Kochte wrote:
It can happen. Very unlikely, but it can.
> >In any event, what Jerry was trying to illustrate is simply that the
Gotcha.
> >Be careful your adjective "larger". Do you mean more volume or more
I understand your questioning of Weber's decision. I don't get it myself. I'm
sure Weber had some mad scheme in mind when he came up with this (or it was a
result of poor understanding of stellar physics, don't know)
> >IIRC (without having all my texts onhand and no time to spend going
Bingo!
> >Don't hurt your head on this stuff. Find a good PSB solution. :-)
If you need help finding stuff, let me know. I can always go through my stack
of books for stuff (barring that, there's a library upstairs...)
> At 2:17 PM -0400 8/7/01, Mark 'Indy' Kochte wrote:
> It can happen. Very unlikely, but it can.
Something different would have to change. The limit is based on the amount of
mass that is after the chromasphere and other mass has been ejected, this
lowers your mass of the sun even further from the threshold.
> I understand your questioning of Weber's decision. I don't get it
I think its because most astronomy books list stars only by spectral type and
occasionally include the size. But not the mass. You can extrapolate, but its
not very easy...especially if you don't know the correct values to apply for
both types.
> If you need help finding stuff, let me know. I can always go through
I may need a catalog that gives solar masses. From that a table (you've got to
have a playing field to base things on) you get a good idea of how big the
system is. A randomization factor for size of star giving size of planets and
thus moons would help. (Is there a planetologist in the house?)
AFAIK in my programming years, I remember running across a couple of stellar
generators. It would spew out a random star, with a random, within known
astronomy parameters, number of planets, given orbits, moons, belts, etc. You
could even, IIRC, get a specific age and what that system looked like. You
could seed the initial variables, IIRC, like primary mass/type/age, etc.
With a little looking, I'm sure you could find it. I even remember one that
was a really pretty screen saver, displaying the system through time (orbits,
ort cloud, comets, etc.). The program generated several flat files that were
read by the screen-saver portion, with the flat files containing all the
info for the system.
Rand.
> I may need a catalog that gives solar masses. From that a table
I'm not sure I agree with this radiant energy inefficient drive / only
way to drive a machine is to light stuff on fire crud.
While I'll admit, solar sails aren't as useful out of system, or in bound,
they are an example of a difference.
However, assuming a fission/fusion drive (take your pick, either are
likely to be dirty) and a ship headed IN bound, with the right shielding
(Absolutely necessary to some extent just to protect the crew) why would
there be _any_ emmisions heading towards the system? Last I checked EM
radiation doesn't bend around corners without help or special very narrow
appatures (and I would not qualify an SDN's main engine cone to be a narrow
appature).
How about magnetic shielding that already goes on? Shielding that
contains plasma's? Ones that can theoretically hold point-anomalies
(not sure that's the proper vocabulary for a tiny black hole)?
However, if you insist that it does, why not use compressed gas? Gaussian
marble throwing? Both throw stuff, but neither emits anything really
detectable beyond a very small bit of space...
Basically, I'm trying to understand how a species who invents hyperdrive,
gravity control, "shields," can't think of a way to hide thier emissions.
Specifically, a species that's shown just how creative it can be when waging
war on itself... One that already knows the military value of being sneaky.
Rand.
> Unlikely. After all, if you're using constant acceleration with
> On Aug 07, Randall L Joiner <rljoiner@mindspring.com> wrote:
Not quite correct. What I'm saying is that I'm assuming a reaction drive (ie a
drive that operates in accordance with Newton's
3rd law of action / reaction -- in order to accelerate forward, you
HAVE to toss something else back). Any other drive violates conservation of
momentum, conservation of angular momentum, and conservation of energy. I
prefer not to introduce that unless I have to.
> While I'll admit, solar sails aren't as useful out of system, or in
They're also VERY easy to detect. How does a solar sail work? By reflecting
sunlight. That means it's a) as big as you can make it, and b) as reflective
as you can make it. This means that it's VERY
easy to detect (as much so as a high-thrust reaction drive? maybe
not, but still dead easy for any nation that can build telescopes with today's
technology).
> However, assuming a fission/fusion drive (take your pick, either are
Because the drive plume itself emits EM radiation. A drive is efficient in
direct proportion to the temperature of the reaction
mass emmitted. This means that a high-temperature exhaust mass allows
you to go farther for the same fuel. For high-thrust you want to
reduce the temperature somewhat from the optimum, but you still want a VERY
hot reaction mass to allow you to get up to any reasonable speed without
needing far too much fuel. This means that your drive plume is also expanding
after it leaves your ship (at a velocity roughly proportional to its
temperature). This means that the drive plume will be emmitting
strongly (for any realistic high-thrust reaction drive, the
emmissions will be up in the x-ray regions probably) and those
emmissions will be coming from a plume that's probably several light-
seconds in length (definitely in the tens of thousands of kilometers) and at
least a few hundred km in diameter. If your ship will occlude THAT, the
defenders are screwed whether they detect it or not. Also, of course, you have
to slow down eventually. At the half way point, actually. Once you do, your
drive plume is pointing right at the place you're heading for. Even easier to
detect. I hate to bring in another list, but the rough consensus on
sfconsim-l (backed up by an astronomer, also the person who wrote
the "definitive sensor rules" for Traveller's FFS2(?), Bruce
Macintosh), is that a high-thrust, high-efficiency reaction drive
would be naked-eye visible out probably to the asteroid belt (even
with the ship in the way) and detectable by telescope significantly beyond
Pluto's orbit (for reference: today's telescopes would allow us to detect the
drive plume from the Space Shuttle's main engines as far out as Pluto, and its
manuvering thrusters as far out as the asteroid belt).
> How about magnetic shielding that already goes on? Shielding that
I'm not sure what you mean by this.
> However, if you insist that it does, why not use compressed gas?
Compressed gas: at what temperature? If it's at a high temperature, it'll BE a
drive plume (thus detectable). If at low temperature, then you will need
incredible tankage volumes to have ANY delta v (required by laws of physics,
not technological assumptions, unless you can create this 'compressed gas'
from a vacuum). Gaussian marbles are even less efficient. To get even a
100km/sec velocity out of them (with a mass driver tube of a mere 1km
in length), with 99.999% efficient mass drivers, they'll emerge from the
barrel with a temperature in the thousands of degrees (inductive heating). The
strain on your railgun will also be considerable. And the thrust produced not
all that much. I can do the math on this one, if you'd like (the others are a
bit advanced to try without my reference books).
> Basically, I'm trying to understand how a species who invents
The big reason is these pesky little things called the laws of physics.
Unfortunately, they place limits on how well you can do things.
The other big reason is that space is an INCREDIBLY sensor-
friendly environment. If the detectors and the countermeasures are at the same
technology level, or even close, you can't hide. Sensor ranges will vastly
exceed weapons ranges unless you assume an incredible advance in stealth with
no advance in sensors (and probably break a few laws of physics while you're
at it).
Actually, it takes light almost 8 minutes and 20 seconds -- to reach the
Earth from the Sun.
--That puts Earth to Pluto about 5 hours, 32 minutes, 48 seconds -- at
their closest approaches.
"Space is big...."
Donald Hosford
> Ryan Gill wrote:
> At 7:02 PM -0500 8/6/01, David Rodemaker wrote:
snippage!
> >You may want to give some thought to C&C ala SFB...
snippage!
> >
I like your calculations. Figuring how big to make the grid is the easy
part...ever tried figuring out how big the map sheet will be?
120 hexs across at about 5/8ths per hex (assuming hexs for 1/2"
counters) is about 75" square. Thats about 6.25 feet on a side. Enormous map!
Not everyone has access to that much room for a single map.
Donald Hosford.
> Ryan Gill wrote:
> At 6:44 PM -0400 8/6/01, Laserlight wrote:
*blink*
I'm not quite sure I follow your view of physics...
> I'm not sure I agree with this radiant energy inefficient drive /
1. Why assume a reaction drive? You have alien species (I've seen zero
exclusion and lots of all encompassing statements here) that use
"grav-drives." While I don't recall fluff ever mentioning one way or
another, its a dead bet they aren't talking about reaction drives... Not if a
ship can change course without changing facing or using a duct porting
or multi-directional porting.
2. No, other drives, that are not reaction drives (in the classic sense,
specifically the one you're using, "heating of a reaction mass and expelling
it out opposite to the direction you want to go) don't violate physics. Ion
drives (no real appriecable heat, "coherent" and single
directional exhaust), thier cousin the Laser drive (Man-Kzin wars, first
book, IIRC first story, is a wonderful example, as well as a really solid
read), pulsed fusion drives (long one to explain, but coupled with charged
particle fuel and magnetic "shielding" can be finely tuned such that all
expulsion is coherently directed, and given the D-He^3 reaction all by
products have zero residual radioactivity... theoretically. Check out Project
Orion, IIRC), then there's the grail of drives, the antimatter drive: The end
result are gamma rays, but during the process, the creation and vector the
rays will have can be controlled such that all radiation can be coherently
focused into one strait line vector (no "backlash," and unless you're directly
in the line of these rays, no detection). This is also been termed the photon
drive (not for "light" but the real definition, discreet packets of energy).
I'll discuss the vacuum energy drive later.
> While I'll admit, solar sails aren't as useful out of system, or in
1. They do not just use light. They use the solar wind which is radiation,
yes, but particles as well.
2. Given a proper "deflection" angle such that the angle of reflection is not
directed at the sensor, you won't see it. Practical experiment. Take a mirror,
and a flashlight in a darkened room (recommend some "navigational" light be
used to avoid harm). Place the mirror at arms length (in hand) pointed
directly back at your eyes. Take the flash light, point it at the mirror, such
that it is directly at or below eye level but does not impede your sight. Turn
flash light on. Now, after you've blinded yourself, twist the mirror in any
direction. Note how the light no longer stings your eyes. Not how just a
slight tilt is all that is needed. True, a slightly tilted solar sail will not
let you travel directly towards an object if you keep the sail angle constant.
It's up to the reader to go learn basic sailing, specifically the word
Tacking. [sp?]
As to your points A and B. A. The size affects the acceleration. If you don't
mind smaller acceleration, you can use a smaller sail. B. See point 2.
Further, reflection of light is NOT reflection of particles, or higher
radiation. Either of which is preferable to light. Higher energy radiation
imparts more speed per area of sail. Particles provide higher mass, thus more
potential energy (yes it's kinetic in a manner, but it can also be argued,
relative, that it is moving at slower speeds).
> However, assuming a fission/fusion drive (take your pick, either are
The drive plume only emits radiation if, and only if, it has the energy to do
so. There are other factors, all of which can be reduced to a level underneath
the cosmic static, such that they are undetectable.
Why this would be done-
Inefficiency. Any energy NOT used to propel the craft in the direction it
wants, is wasted. Heat, light, etc, are all _by-products_, undesirable
at that, of a burning reaction engine. Idly, the only energy you want expelled
is the kinetic force applied to allow you to thrust. Thus, if a plume is hot
(radiation or heat), it's inefficent. Now, there are reasons why you may
accept this inefficency (hot implies more energy, thus more thrust), true, but
that doesn't mean in 10 years, much less hundreds, that we won't have solved
this inefficiency. Specifically, there are theoretical models already being
looked at that do solve various parts of this inefficiency.
To disabuse you of a false notion, heated/burning reaction engines are
the
_least_ efficient model of engine we know of. They just happen to be
easiest/cheapest to use currently.
> This means that your drive plume is also expanding after it
Expansion does NOT equal emmision. As I pointed out early, a compressed gas
system (assuming a non heated non irradiated gas) is the counter to your
declaritive.
I never said the ship would occuled the plume, only the reaction that causes
the plume.
> Also, of course, you have to slow down eventually. At the half
Point well taken. But not necessarily true for all values of "engine" or drive
plume. Again, a compressed gas is the counter example. (I know, I over use
this one, but it fits well, is a simple mechanic using simple
physics, and is doable _now_, not just theoretical)
> I hate to bring in another list, but the rough consensus on
If you hate to do it, then don't. Specifically, I'm not on the list, and so I
have no reason to beleive anything posted of it or about it. I've not
read or had the chance to "check-out" the so called astronomer to verify
that the person is who they say they are, and really does know what they are
speaking of. And given the nature of the net, this is a necessity... To many
people pose as something they are not out there.
Next... An astronomer is NOT a rocket scientist. (sorry, had to be said)
And someone who writes Sci-Fi is no more likely an expert on science
(much less a particular branch) than the next joe who walks by me.
A high-efficiency drive of TODAY may be, but of tomorrow? I'll again
point
out the by-products of light and how inefficient that is.
> How about magnetic shielding that already goes on? Shielding that
Magnetic shielding (used today) can contain and control a plasma, it can be
used to simply hold, or to duct/vent it in a desired direction. It can
completely shield the emmisions of the plasma. Any and all emmissions.
> However, if you insist that it does, why not use compressed gas?
Gas!= plasma. 2 completely different states of matter, thank you.
You missed one of the fundamentals of gasses... PRESSURE. (Thus the term
compressed)
Given tough enough containers, amazing preasures can be had. Given that (in
another thread) we've spoken about the hulls of these craft withstanding
nukes, is it to hard to imagine a container that can withstand amazing
pressures by todays standards?
*shrug* There's a bunch of math and basic physics here, that I really don't
want to get into, but it can be done.
A compressor only requires energy to run. Hydrogen is loosly abundant in
space. (space is not empty) An excercise for the reader: lookup Bussard
Ram-Scoop engine.
On a separate path, but relevant in reply to your above paragraph: The vacuum
energy drive: Without going into the quantum physics of it, let me state this,
and let the reader do the research (and headache): Quantum theory and General
Relativity both show that a vacuum has a very large positive value of energy
per unit volume. Richard Feynman estimated two billion tons per cubic
centimeter. Based on the Casimir Effect, Richard showed that a small amount of
energy could be produced from vacuum energy. Others, such as Harold Puthoff,
have theorized (but not proven) that much larger amounts can be produced.
Check out "All the Colors of the Vacuum" by Charles Sheffield, or Arthur
Clarke's
"The Songs of Distant Earth" for sci-fi examples. (By use of sci-fi,
I'm talking hard sci, with fi built around facts, not fluff, which is hard fi,
with pseudo sci)
> Gaussian marbles are even less efficient. To get even a
Efficient how? In acceleration? true. In by-products? Depends.
Inductive heating can be controlled, thus allowing lower force acceleration.
But it's still viable.
You're welcome to do the math. I've seen it. However, I'd like to point out
that current tests have shown a effective jet velocity (EJV) of up to 8
km/sec. This is almost double what is currently used to day for
chemical
burning, liquid oxygen/liquid hydrogen (LOX), which has an EJV of
slightly
more than 4 km/sec.
That's without superconductors.
> Basically, I'm trying to understand how a species who invents
They're wonderful things. And if you want to talk about them, I'm happy to.
Specifically in regards to space flight, in relation to today, near future, or
far future. However, I do request that you bone up on said
physics, especially recent practical/applied physics in regards to the
subject.
> The other big reason is that space is an INCREDIBLY sensor-
This is a totally different arguement, to which I STRONGLY disagree.
Space is very very very very sensor unfriendly. Though size alone, the
problems are astronomical... (Had to use the pun!)
As a 2 part excercise for the reader... Part A: Given X distance from
target Y, what size linear/circular wall/plate is necessary to block
(occlude? Damn, I need to invest in dictionaries instead of physics books)
view of any sort of object Z (at point X) by target Y, given that the plate is
impenatrable to view. Hint: easy answer, assuming no angle, is: diameter of
object Z. Part B: given a "plume" that stretches length A behind object Z,
what, if any, changes are necessary to Part A's answer. Hint: easy answer, to
follow Part A: diameter equal to the greatest diamter of plume. (for ease of
math, question was stated where answers in 2D or 3D will be accepted)
Anyway, enough for tonight. My question still stands.
> I like your calculations. Figuring how big to make the grid is the
counters) is
> about 75" square. Thats about 6.25 feet on a side.
Your answer in correct only if viewed from a point on the direct line of the
flight from the destination.
The ability to have a picket on a moon, asteroid, planet or anywhere in space
means that the plume would have to have zero emissions or be enclosed entirely
or it will be detected.
Even if you have a linear plume (questionable as even a laser expands as it
travels), it will interact with stuff in space. As you pointed out space is
not empty. Your plume will interact with the free hydrogen and dust when it
collides with it. At that point your plume will no longer be linear, it will
at best be splintered into a linear portion and a pulsed linear splinter.
As for reactionless drives, the chance is that if we can manipulate something
enough to push a SDN around at 4 Gs acceleration (or more), that we will find
a way to detect it from a distance.
-----
Brian Bell
-----
[quoted original message omitted]
> At 4:23 AM -0400 8/8/01, Donald Hosford wrote:
counters) is
> about
Well, I'm looking at the possibility for two maps. One for the Ship actions to
be fought on. And one for the players to move stuff around on. The large size
of the map would allow for a good area of play. If one wanted to go smaller
you could of course. The trick is to be sure it scales up. The advantage of
having just task forces and not entire ships is that you could sit down and
note each down based on Hex numbers and revisit the game over several
successive days. Another idea would be a wall mount map with adhesive or
slightly tacky
icons/labels for the task forces/blips.
A 6'x6' wall map would work well I think. Laminate it and you could use grease
pencils ala the Ops rooms on board ships. (Nice because your situation maps
don't crash if they are grease pencil marks.)
> Donald Hosford.
> At 8:35 AM -0400 8/8/01, Laserlight wrote:
Yes, but Space is Big. Really Big, you have no idea just how big space really
is. You may think its a long way down to the
chemist....sorry...
One could naturally go with a smaller map of course. Smaller star and fewer
interesting planets in the system.
> Yes, but Space is Big. Really Big, you have no idea just how big
20hex radius can be made to fit on a couple of sheets and will let you get
> On Tue, 7 Aug 2001, Randall L Joiner wrote:
> AFAIK in my programming years, I remember running across a couple of
You
> could seed the initial variables, IIRC, like primary mass/type/age,
I don't have web access at this instant, but I'm sure I've got several
links like that on my website - see
<http://warbard.iwarp.com/links3.html>
and have a look at the Space Science/Astronomy links area.
Brian - yh728@victoria.tc.ca -
- http://warbard.iwarp.com/games.html -
> With a little looking, I'm sure you could find it. I even remember
I thought about this alot...and I came up with these two possible answers:
A) Use two maps for the system. They would divid the system into Inner and
Outer zones. One hex on the outer zone map would equal the entire (or most
of) inner zone map. movement/turns on the outer zone map would be
scaled to several turns on the innerzone map. (I think...)
B) use a stylized map. Give each body, ect in the system it's own orbit ring.
Sun in the center, 1st planet in the first ring, second planet in the second
ring, ect. The problem with this idea is how to scale it. Each orbit is not to
proper size in relation to the other orbits. But it does make the map smaller.
(I think it's only good point.)
Donald Hosford
> Ryan M Gill wrote:
> Yes, but Space is Big. Really Big, you have no idea just how big
> Ryan M Gill wrote:
> Well, I'm looking at the possibility for two maps. One for the Ship
I like this idea. And it leaves the table free for the battles.
> At 5:32 AM -0400 8/9/01, Donald Hosford wrote:
I thought about that as well, the separate map concept seemed cumbersome to
me. I got worried about the flow from one to the other being difficult.
When I looked closely at doing the hexes as.5 AU size, it seemed to work out.
Mercury was right up against the Sun's Hex and all the others either fell on a
hex ring (there abouts) or on the edge. Yes, I've actually drawn this out....
> B) use a stylized map. Give each body, ect in the system it's own
The anal retentive person in me just doesn't like that. If I can do something
and make it look damnably real, then I will.
(ie, I've been making infantry fighting positions for SG, they are built just
like they really are, two fighting positions with overhead cover, slots for
firing on the oblique and side and rear cover. I've
just finished flocking them, next is brush, camoflage netting/tarps
and rocks.)
> At 5:34 AM -0400 8/9/01, Donald Hosford wrote:
Yep! You could even do an extra 2' on the edges for the deepspace areas.
Donald said:
> >A) Use two maps for the system. They would divid the system into
Maybe as an optional "I want to raid Pluto" thing, but I would want to have
95% of the action occuring on one main map.
> >B) use a stylized map. Give each body, ect in the system its own
Makes accurate movement impossible. Since the point of this exercise is to
Well.
This is a particularly interesting discussion - for a layperson with
*no*
background in this sort of subject (well, other than high-school
physics). That business about vacuum energy drives is fascinating...
I've gotta add in, however, that the discussion would be more enjoyable
without the nasty edge.
How about ratcheting down the pomposity level a few notches, and just make
your points?
Either you're being sarcastic and snippy in an attempt to be funny (which it
isn't), you aren't reading what you write and don't realize what you're
saying, or, hopefully, you're just really tired or something...
Please remember, the general membership of this list might not be
astrophysicists or rocket-scientists - but we're not stupid.
<snip>
> Practical experiment. Take
<snip>
> To disabuse you of a false notion, heated/burning reaction engines are
<snip>
> Expansion does NOT equal emmision. As I pointed out early, a
<snip>
> I hate to bring in another list, but the rough consensus on
> If you hate to do it, then don't. Specifically, I'm not on the list,
<snip>
> Next... An astronomer is NOT a rocket scientist. (sorry, had to be
<snip>
> 2 completely different states of matter, thank you.
<snip>
> You missed one of the fundamentals of gasses... PRESSURE. (Thus the
<snip>
> space. (space is not empty) An excercise for the reader: lookup
<snip>
> You're welcome to do the math. I've seen it.
<snip>
> They're wonderful things. And if you want to talk about them, I'm
<snip>
> As a 2 part excercise for the reader... Part A: Given X distance from
> Hint: easy answer, assuming no angle, is: diameter of object Z.
> Hint: easy answer, to follow Part A: diameter equal to the greatest
> (for ease of math, question was stated where answers in 2D or 3D will
<snip>
********************************************
The distance scale is easy, what about the time scale?
For example, take as a base...
1 MU = 1000 km and 1 Turn = 15 minutes
Maybe not THE standard, but does allow a convenient 1g = Thrust 8;)
At 1 MU = 1 hex = 1/2 AU, the distance scale is 1:74,799.
Keeping the same time scale would put a turn at 2.133 YEARS.
To allow any sense of reasonable reaction times, you would need to break the
movement into impulses (sorry, no better term comes to mind).
Lets take a smaller scale just for example...
1 MU = 1 hex = 2.88x10^6 km and
1 Turn = 1 30-Day-Month = 4 1-Week-Impulses
At this is scale of 1:2880, most fleets from FB1 can move 1 hex per week (NSL
capital ships can move only once every other impulse) from a standing start,
and if Earth (52 hexes from the Sun) and Mars (79 hexes from the Sun) were at
their closest points in their orbits, like they should be on 19 Jan 2183, they
would be 27 hexes apart.
This FB1 fleet starting at Earth moves 4 hexes on turn 1,
turn 2 thrust +4 for 8 hexes (8 hexes total),
turn 3 thrust +2 for 10 hexes (18 hexes total) and turns around (Cost?),
turn 4 thrust -4 for 6 hexes (24 hexes total),
turn 5 thrust -3 for 3 hexes and arrive at Mars (27 hexes total),
and finally thrust -3 to stop inertia on turn 6 and enter Mars orbit 6
months later.
I can hear you now; don't you know that the planets move? So, just move Mars
24 hexes in orbit around the Sun each month (6 hexes each 1 week impulse) and
have fun working out your own movement plot.
Note, this does nothing for the size of your map, but make it bigger, 160
hexes wide and just the inner planets. But the time scale is at least a little
more workable, I think.
Now you could skew the distance to time scales if you want, and I'll leave
that up to you.
> At 1 MU = 1 hex = 1/2 AU, the distance scale is 1:74,799.
Huh? I have no idea how you came out with this, but work out how long it takes
to do.5AU at a constant thrust of 1g. I predict you'll be amazed at how short
a time it is. The formula is distance =.5 * acceleration *
time^2 -- that's for straight acceleration through to the end point,
you could also work the time to get to the halfway point, then double that
time, if you want to arrive at your end point at zero velocity (relative to
your
start point, not necessarily relative to the planet/ship/etc you're
meeting).
I can't find it now, but didn't Jon (GZG) send out email that talked about how
ships jumped in system? It's been at least a year or two ago. If I remember
correctly, ships made a few in system jumps on the way in to get closer to the
inner planets.
That would seem to save a lot of time vs. normal space transit.
Nathan
[quoted original message omitted]
The jump procedures are in the back of FB1 (p. 44-45). It indicates that
MINIMUM between jump time is 6 hours, with 1 day or more being the standard
in non-critical (war, emergency, etc.) situations.
So if the transit time is less than 24 hours in a non-critical situation
(6
hours in a critical situation), it MAY be better to jump. But you also must
weigh the stress on the crew, the time to restart the ship AI and the time
reoganizing the fleet after jump drift.
-----
Brian Bell
-----
[quoted original message omitted]
> At 10:01 AM -0400 8/10/01, Jerry Cantrill wrote:
hold on there... I'm really only expecting the Fleet Action to be a
matter of 10-20 turns worth of game with each turn being several
hours.
The particular goal is to arrange thing such that battles in ship scale have
more of a reason to be arranged other than "so you're in space facing off
against this other force of ships".
The times scales will likely not work out very well. Thats not the goal here.
Remember, there is some suspension of disbelief (FTL isn't possible
remember...).
> Ryan M Gill wrote:
> The times scales will likely not work out very well. Thats not the
Says who??? Oh, you mean Them(tm) (are you *with* Them?). Well, They were
pish-pashing the potential of breaking the sound barrier, too...
;-)
> At 11:44 AM -0400 8/10/01, Indy wrote:
Ok, ok. ...yet.... :-P
1g acceleration = MD 8? 1G seems awful slow.
Perhaps 1mu = 10,000km would be better
This is about 15 minutes at 1.25 Gs = Thrust 1.
Using this, at MD 1, an AU could be crossed in 31 hours constant acceleration
or 62 hours from stop to stop (with 0 turn around time).
At MD 2, it could be done on about 22 hours and 16 hours at MD 4 (again double
for stop to stop).
So unless you have very fast ships, it appears that
the trade-off between jumping and normal space
transit is at sizes of about 1au for stop to stop MD 4 fleets.
> >1 MU = 1000 km and
Caveat all this assumes that I remembered the formulas, created the Excel
expressions, input the data and transcribed the results, all correctly.
I come up with Thrust 1 = .25g (which is why I prefer 450 second/7.5
minute turns, that gives you 1 thrust at 1g = 1000km displacement on that
turn)
.5 AU = 75 000 000 000m
t = sqrt (d/.5a) = sqrt (75 000 000 000/(.5 * 2.5)) = 244989 sec = ~ 68
hours to go.5AU at thrust 1.
Your speed relative to your start point is 612km/sec.
Just for fun, let's go 60 AU (across Neptune's orbit from one side to the,
accelerating all the way, diving straight through the sun, and not worrying
about relativistic effects) -- how long does that take? 31 days.
> Ryan M Gill wrote:
> At 5:32 AM -0400 8/9/01, Donald Hosford wrote:
I agree with you here. Having two maps does make possible "move" errors.
> When I looked closely at doing the hexes as .5 AU size, it seemed to
Sounds interesting...how big was the resulting map? Maybe I could make a wall
map for grease pencils...
> >B) use a stylized map. Give each body, ect in the system it's own
Each
> >orbit is not to proper size in relation to the other orbits. But it
One thing I don't like about my second idea, is the complexity involved in
moving from one planetary ring to another.
> (ie, I've been making infantry fighting positions for SG, they are
Got any pics of em?
> --
> Ryan M Gill wrote:
> At 5:34 AM -0400 8/9/01, Donald Hosford wrote:
That would look cool!
> --
> Chris DeBoe wrote:
> Donald said:
Yes...both ideas have their flaws...I thought I should run these "up the pole"
to see if others saw the same flaws as I do...
> At 4:01 PM -0400 8/10/01, Donald Hosford wrote:
It seems like I got a 11x17 map with something like 1/8 inch hexes.
This would be good for planning and mapping...
> One thing I don't like about my second idea, is the complexity
Its too heavy. The component for moving from Fleet Action Scale to Ship Action
Scale will be a rough clock face bearing and the speeds will probably have a
fixed scale if you are at 1 hex per turn then
you can have a speed of 0-5 MU/turn entry....
I fully envision games where astute players will have Kra'Vak running them
down to keep the rail guns at longer reaches while the Kra'Vak are forced to
brave a larger duration of accurate Beam fire before they are able to get into
closer Railgun range.
> > (ie, I've been making infantry fighting positions for SG, they are
Not yet. I need to get a camera at some point so I can take lots of photos and
get them up.
> At 12:03 10/08/01 -0400, you wrote:
Oh great, the Phalons shoot balls of plasma 120 000 kms across (6MU attack
radius of the Plasma bolt):)
> At 9:48 AM +1000 8/11/01, Derek Fulton wrote:
Ummm, Jon, what sort of times scale did you envision ships transiting in and
out of systems in? Days? Weeks? Months?
My time of 2.13 yrs per turn was without FTL jumps. But with them you don't
need a straight hex grid to represent a solar system. Since the distance a
ship can (safely) jump increases as it moves away from the star, and the
distance between the orbits of the planets also increases
as one gets farther away from the star. The star/planets system could be
represented by concentric range bands of maybe 1MU = 1Jump, the distance of a
(safe) FTL Jump at that orbital band whether it has a planet or not. The
farther planets distances apart could be reduced this way as you will probably
be jumping to something and not to the empty space between. Each 1 Day turn
you move 1 MU from band to band or along the current band. Or if a military
fleet was in a hurry, they could move 4 MU (1 jump every 6 hours). Note my use
of safe jump, if you wanted to push it, allow longer jump movements with a
penalty of risk of misjump similar to how FT2 described FTL entry.
Sounds like you have a simple workable system there...
Donald Hosford
> Jerry Cantrill wrote:
> My time of 2.13 yrs per turn was without FTL jumps. But with them you
Jeery Cantrill said:
> My time of 2.13 yrs per turn was without FTL jumps.
And apparently without continuous-acceleration drives either. How
*did* you come up with 2.13 years?
To add some additional tactics to it...
You could postulate that the MD rating of the engine also translates to the
FTL rating of the ship (larger engine produces greater power to shunt into
jumpspace and larger objects need greater energy to jump).
If you factor in the PSB on p. 44 of FB1, you could set a ship's maximum
_safe_ jump rate is equal to MD-1 in light years. This, of course, gets
proportionally smaller as you enter the gravity well of a system (agian PSB
from p. 44-45).
It would then be easier to make concentric rings for the system with each
ring closer to the center being at -1. Thus slow ships (BDN, SDN, etc.)
would need to spend a greater proportion of thier time in normal space
transit, while fast ships (couriers, etc.) could jump from further down the
gravity well. This would cut thier transit time and give a stategic reason for
engines to cost as much as they do in mass and points.
> At 7:53 AM -0400 8/13/01, Bell, Brian K (Contractor) wrote:
This really really hamstrings the NSL strategically. Tactical movement seems
disconnected (engine wise) from strategic movement.
True, but from thier design philosophy, I always assumed the NSL was primarily
a home defense priority fleet anyway. For raiding or attacking you would need
faster designs.
> At 10:31 AM -0400 8/13/01, Bell, Brian K (Contractor) wrote:
Aside from their smaller CA's and BC's nothing is relatively fast.
I definately agree that strategic movement rate should not be connected to
main drive speed, because of the disadvantage this gives the NSL (and any
other fleets that consider MD a low priority), and also because I doubt the
connection between sublight drive rating and the power the ship has to go
around. Surely the fusion reactors in NSL ships are as good as anyone elses?
It's only their drives that are less powerful. Mainly though, I feel it's
easier to keep everyone on an equal footing strategic-speed wise because
it saves complication and makes it easier to keep things fair. Just my
opinion.
> On Fri, 10 Aug 2001, Jerry Cantrill wrote:
> The distance scale is easy, what about the time scale?
The only problem with this scale is that it would be impossible for any FT
ship to actually take off from nearly any planetary surface at all, if Thrust
8=1g. You'd need something impossible like Thrust 20 to take off from a 1g
world...
Or am I missing something here - assuming atmosphere-capable starships
take off airplane style (horizontally) would T8/1g be enough to get you
off Terra? What about lower thrusts? T6?
Granted, most FT ships aren't even capable of atmospheric reentry, never
mind landing, but some are, especially the smaller ones - DD & down.
In a message dated 8/13/2001 5:53:14 PM Mountain Daylight Time,
> yh728@victoria.tc.ca writes:
<< The only problem with this scale is that it would be impossible for any FT
ship to actually take off from nearly any planetary surface at all, if Thrust
8=1g. You'd need something impossible like Thrust 20 to take off from a 1g
world... >>
Technically, you could take off straight up with a thrust of 8.0000~01 and
eventually reach escape velocity.:o)
(It would just take forever and a LOT of fuel:o)