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FrankTrollman
So 2071 is the time when Mars gets closest to the Earth as it does every 17 years (the last one was 2003). Using Shadowrun technology and the rules presented in Target: Wasteland, one is able to accelerate at one Gravity (9.8 ms/s^2) pretty much all day. And that's fine, because with one day of accelerating at that speed, and one day slowing down at the same rate, you'd have gone 78 million kilometers.

That's convenient, because that's the distance from the Earth to Mars in 2071. Assuming you have sufficient fuel (and you do, because you are refueling your plasma jet on a stable space platform), you can get to the orbit of Mars in just oer 2 days. You could potentially have a mars mission that lasted less than a week.

Yeppers, that's 86,400 seconds a day, for a mid-point velocity of 847 kilometers per second. That's less than 1/3 of 1% of the speed of light, so you can still handwave off relativistic effects. The best part is that the entire trip (except for a hurlariffic experience at the beginning, middle, and end of the trip) would be spent at acceleration equal to normal Earth Gravity. In short, the plasma jet would propel you through space fast enough that it would feel just like you were sitting in a normal room on Earth.

-Frank
fistandantilus4.0
New Space Race?
ChicagosFinest
Where going to figgure out if those dragon bones are real or not!!! Secondly is the mana on Earth going to get all wacko? What about the two dragons rifts?! Ohh the opportunities galore.
knasser

Can SIMs simulate gravity? I presume they can because otherwise you'd never be able to have a SIM of swimming, or falling off something, etc. So the ship may be entering Mars orbit but the pilots are having tea in a virtual living room. Of course the pilot has a shed-load of read-outs in his morning paper. smile.gif

But I'd question the Target Wasteland figures for sustaining that acceleration. I don't have it - what sort of technology provides that? Because assuming the ship were 5,000kg (a tin box with people in it), that's about 3x10^14 joules. You could probably run New York city for an hour off that.
Demerzel
See now you're making me dust off Marion and Thornton to brush up on my Transit Orbits...
Demerzel
Well, okay. This is a less than simple problem.

Consider the space shuttle orbiter alone weighs more than 100,000kg(wiki) and do you really want to take less than that to Mars?

How much of that should be reaction mass? Let's say 10%. So 10,000kg of fuel. Two days there and two days back that's a dm/dt of roughly 10,000kg/96hours = 0.0289 kg/second.

To get 100,000kg accelerating at 9.8m/s^2 you need 980,000 N Thrust.

Making the horrible assumption of ignoring relitavistic effects that requires the ejectant to be going around .28c.

Not too reasonable even in 2070. Well what if we tack the orbiter sized object onto a 900,000 kg fuel tank and use that much fuel...

900,000 kg / 96 hours = 2.60 kg / second.

Thrust needed is 9,800,000 N.

So now the ejectant is just going roughly .01c but that requires you launch one million kg into orbit...

Keep in mind this is super rough, it's almost 4am and I don't really stand by this as more than back of the envelope calcs.

It throws out earths gravity making it more difficult (This is rocket in free space cals). So it'll be harder by a long shot...

I don't imagine this is the most cost effective way, a much longer trip would allow for significantly less fuel and be way mroe cost effective...
ChicagosFinest
In english?
Konsaki
To hit that speed based off the weight of the spacecraft, you need more fuel. Adding fuel means adding more weight, and in turn requires more fuel to hit that speed.

It would be more cost efficient to take a few more days to get there and save alot of fuel and money.
Steak and Spirits
QUOTE (Konsaki)
It would be more cost efficient to take a few more days to get there and save alot of fuel and money.

Nonsense! Afterburners, full steam ahead lads! Avast ye, earth-lovers! Watch tha' starboard bow!
Demerzel
QUOTE (Konsaki)
To hit that speed based off the weight of the spacecraft, you need more fuel. Adding fuel means adding more weight, and in turn requires more fuel to hit that speed.

It would be more cost efficient to take a few more days to get there and save alot of fuel and money.

But if you put it that way on DSF someone will inevitably say, "Yea? Prove it."

I'm not a gun nut so I can't really contribute to those super technical posts, but I can do rocket science!
Konsaki
QUOTE (Demerzel)
QUOTE (Konsaki @ Nov 5 2006, 08:46 AM)
To hit that speed based off the weight of the spacecraft, you need more fuel. Adding fuel means adding more weight, and in turn requires more fuel to hit that speed.

It would be more cost efficient to take a few more days to get there and save alot of fuel and money.

But if you put it that way on DSF someone will inevitably say, "Yea? Prove it."

I'm not a gun nut so I can't really contribute to those super technical posts, but I can do rocket science!

Someone wanted a dumbed down explaination and I figured that was something I'm good at so...
Dentris
Chicago Finest:

It means in order to make a rocket flies out in orbit, you need a reactor powerful enough to beat earth gravity (which is 9,8m/s). The journey is likely to burn through the shuttle fuel reserve completly. Now, if you refuel your shuttle in orbit, you can use the same acceleration (9,8m/s) in space, where their is no gravity, which mean your acceleration is exponential (the first second, you travel at 9,8 m/s, the second second, you travel at 19,6 m/s, the third second you travel at 29,4 m/s, etc.) Which mean at the end of a day, you'll be travelling at a speed of 8467 km/s. The next day would be use to decelarate at the same speed and you'll be around Mars within 2 days.

The problem is the amount of fuel needed to achieve this is gargantuan. You'd need 1000 tons of fuel in the shuttle to sustain so much acceleration and deceleration for that much time. It would be a lot more cost-effective to accelerate for a shorter length of time, stop the engines (and continue to travel at a certain speed because there is no friction in space), then decelerate.

I hope i clarified things a little bit.
Demerzel
@Konsaki,

I don't mean to diminish your contribution, I'm just excited to get to put my degree in Physics to some use.
Digital Heroin
Would I be thoroughly braindead in pointing out that there are alternate possible means of fueling a rocket that no doubt someone will have tried to employ... say nuclear?
ChicagosFinest
Ahh so so magical nukes that keep popping up might be put to good use?
Konsaki
Why not just have 20 mages cast levitate on the ship until it leaves the mana sphere?
ChicagosFinest
and then the nuke blasts to provide fuel
Konsaki
Hell, we can use catgirls for the nuclear reaction instead of uranium or other heavy element. Reduce the catgirl population while reducing the radiation output, win/win!
Dentris
QUOTE (Digital Heroin)
Would I be thoroughly braindead in pointing out that there are alternate possible means of fueling a rocket that no doubt someone will have tried to employ... say nuclear?

Well, the fuel we are talking about isn't gasoline, but Nuclear Pellets...which mean this is already the alternate fuel source you are talking about.

And no, you are not brain-dead; we weren't explicit enough.
Digital Heroin
See, now there's where I go and affirm I am in fact braindead... nuclear pellets? They use them thar tiny bits of plutonium or such today?

*has a tendancy to actually speak with an assumed Georgian accent when feeling dumb, seriously*
Dentris
ok, I'm not a rocket scientist myself. All i know is from the excellent GURPS setting called Transhuman Space and from my friend with a doctorate degree in nuclear science.

The nuclear pellets could (theorically) be used as fuel for fusion reactor. By directing a laser into these pellets, creating microexplosions at the atomical level. Right now, this technology is not yet cost-effective, but in the near-future, it could be developed.
FrankTrollman
QUOTE
Now, if you refuel your shuttle in orbit, you can use the same acceleration (9,8m/s) in space, where their is no gravity, which mean your acceleration is exponential (the first second, you travel at 9,8 m/s, the second second, you travel at 19,6 m/s, the third second you travel at 29,4 m/s, etc.) Which mean at the end of a day, you'll be travelling at a speed of 8467 km/s.


Well, actually your acceleration is constant,
Your speed is linear,
And your distance travelled is exponential.

But yeah.

QUOTE
The problem is the amount of fuel needed to achieve this is gargantuan. You'd need 1000 tons of fuel in the shuttle to sustain so much acceleration and deceleration for that much time.


Why? We aren't talking Newtonian physics here even if we are needing to come up with Newtons to accelerate our ship. Equal and Opposite Reactions come from energy output, not mass differential. Theoretically we could get our acceleration by throwing individual protons out the back if they were propelled with enough force. The cap of C applies to velocity, not energy. In fact, the cap exists because it would take infinite energy to bring any massed object up to a velocity of C - which coincidentally means that you could have any amount of energy less than infinity on any object with mass - in short there are no hard caps to rocketry.

The difficulty then is to accumulate enough energy in the first place to run your plasma jet, not in carrying enough material to supply particles to your plasma jet. For all we know, the materials for that plasma jet could be 5 kilograms - we aren't using futur tech today so there's no way to know. What we can know (or at least guess), is that the craft probably isn't using something more efficient than Fusion to get that energy, and it's made by humans so it probably isn't going to be getting better than 20% efficiency of that for forward thrust.

So sure, let's assume we have a 100 tonne spacecraft. And we're going to be in essentially constant acceleration for the entire 78 million kilometer journey. That's going to take 9.8 x 78,000,000,000 x 100,000 = 7.6 x 10^15 Joules. That's... a lot.

But it's not an insurmountable lot. A 1 megaton hydrogen bomb (which is about as small as they come) produces 4.18 x 10^15 Joules. So if yoiu have a Fusion reactor (which is what a Hydrogen Bomb is), and you have an efficiency of 20%, and you want to go both ways at 1G, your nuclear drive is going to have to be the equivalent of about 20 megatons (because it's much better to err on the side of caution).

That's the size of a "standard" hydrogen bomb today!

Of course, getting a 20% yield of forward momentum out of your Fusion engine and not, for example, creating a short lived sun around the Earth with you inside - that's a problem. But it's a problem that has been solved with Shadowrun technology. Fusion plants produce power and have for 30 years. They don't simply transform areas kilometers across into plasma while exploding they way they do with current technology.

The 2070s are indeed awesome, and comfortable travel to mars over he Weekend is well within the realm of possibility.

-Frank
knasser
QUOTE (ChicagosFinest @ Nov 5 2006, 11:29 AM)
In english?


To keep that sort of accelleration going for that length of time, you're going to need a lot of fuel. And a lot of fuel weighs quite a bit (more properly, has a lot of mass, but this is the simplest the explanation is going to get). So now, your craft is even heavier because of all that fuel, so it needs more energy to push it at those speeds for that long... which means - MORE FUEL!

I was aware of that when I posted, but I kept this out of it until Frank (or someone) answered my question about what sort of power source these ships are supposed to have in 2070, because some sorts of power source are actually off the ship itself, such as lasers fired at it, whilst other sources of power such as nuclear power, have a very good energy to mass ratio, so you don't need to worry quite as much about the problem as you would with regular rocket fuel.

Even if you could focus that much energy in one craft though, the economics are going to make it far far cheaper to take a few months for the journey than to try and burn an entire city's power consumption in a couple of days. In Kim Stanley Robinson's Mars trilogy, he has a ship make the journey in five months, which is considered as fast as economically possible, and that was when there was an urgent need for it. IIRC, anyway.

EDIT: Was writing this before Frank posted his answer. Plasma jets from Fusion reactions answers my question about power source.

@Frank: 9.8 x 78,000,000,000 x 100,000 = 7.6 x 10^16 Joules, not ^15. This brings you to needing around a 90 Megaton bomb equivalent at 20% efficiency. That's way bigger than currently exists, though nowhere near the total that exists. So given the technology (which cannon game seems to support), it's feasible. Still waaaay more cost effective to take a few months instead, though. smile.gif
FrankTrollman
17 days. A fusion drive capable of sending you to Mars over the weekend would be producing enough power to power NYC for 17 days.

Of course, conservation of energy never works for you, and forward motion is a fuck tonne easier to get than electrical power. In reality, you're probably looking at a Fusion reactor that could potentially keep NYC going for a week.

-Frank
Butterblume
Am I a rocket scientist? I studied computer science, mathematics and physics for a few years and have a good background in chemistry. We even built a few (very small) rockets. (I just mention it to establish that I understand most of what were are talking about biggrin.gif)

Anyone remember Project Orion?

I first stumbled upon it in the book Footfall by Larry Niven and Jerry Pournelle.
FrankTrollman
QUOTE
@Frank: 9.8 x 78,000,000,000 x 100,000 = 7.6 x 10^16 Joules, not ^15. This brings you to needing around a 90 Megaton bomb equivalent at 20% efficiency. That's way bigger than currently exists, though nowhere near the total that exists. So given the technology (which cannon game seems to support), it's feasible. Still waaaay more cost effective to take a few months instead, though.


You are quite correct about the 10^16. I misplaced a zero while multiplying large numbers. Sorry about that.

As to whether it's more feasible to go in 5 months, I don't know. If you accelerate at 1/10th of a G instead of 1 G you get there in 6 months instead of 2 days, and you use up 110th the fuel. But is that economical with Shadowrun technology?

People don't survive well at 1/10th gravity for half a year. They really don't. Which means that you'd need some sort of elaborate life support system running continously for the entire period. Probably involving keeping everyone in vats or centrifugingthem for artificial gravity. So really, you have to ask yourself which is more expensive: keeping a team alive in space for half a year (maintaining their bodily functions, supplying food, clean water, artificial gravity stimulus, waste disposal, etc.) or supplying an extra 70 megatons of power for your fusion engine.

And honestly, when we compare the costs of life support to the costs of deuterium, I'm really not seeing the advantage for the slow ships. I don't think that a slow route is economically feasible, while with SR tech, a fast one is. People can jolly well just eat Cliffbars for 2 days - 6 months requires a whole thing.

Seriously, Fusion reactors produce a lot of energy if you can get them to "not explode". A Kilogram of He3 and 2/3 of a kilogram of D can potentially output 6x10^14 Joules - which would cover our energy needs in less than the mass of a Troll. The fuel really seriously isn't a problem. The problem is using that fuel in such a manner that you don't all die - and SR has already handwaved that particular problem away.

-Frank
knasser
QUOTE (FrankTrollman @ Nov 5 2006, 03:04 PM)
QUOTE
@Frank: 9.8 x 78,000,000,000 x 100,000 = 7.6 x 10^16 Joules, not ^15. This brings you to needing around a 90 Megaton bomb equivalent at 20% efficiency. That's way bigger than currently exists, though nowhere near the total that exists. So given the technology (which cannon game seems to support), it's feasible. Still waaaay more cost effective to take a few months instead, though.


You are quite correct about the 10^16. I misplaced a zero while multiplying large numbers. Sorry about that.

As to whether it's more feasible to go in 5 months, I don't know. If you accelerate at 1/10th of a G instead of 1 G you get there in 6 months instead of 2 days, and you use up 110th the fuel. But is that economical with Shadowrun technology?

People don't survive well at 1/10th gravity for half a year. They really don't. Which means that you'd need some sort of elaborate life support system running continously for the entire period. Probably involving keeping everyone in vats or centrifugingthem for artificial gravity. So really, you have to ask yourself which is more expensive: keeping a team alive in space for half a year (maintaining their bodily functions, supplying food, clean water, artificial gravity stimulus, waste disposal, etc.) or supplying an extra 70 megatons of power for your fusion engine.

And honestly, when we compare the costs of life support to the costs of deuterium, I'm really not seeing the advantage for the slow ships. I don't think that a slow route is economically feasible, while with SR tech, a fast one is. People can jolly well just eat Cliffbars for 2 days - 6 months requires a whole thing.

Seriously, Fusion reactors produce a lot of energy if you can get them to "not explode". A Kilogram of He3 and 2/3 of a kilogram of D can potentially output 6x10^14 Joules - which would cover our energy needs in less than the mass of a Troll. The fuel really seriously isn't a problem. The problem is using that fuel in such a manner that you don't all die - and SR has already handwaved that particular problem away.

-Frank


Neither of us can put a price on life-support systems on a space ship in 2070 in a fictional universe, or costs of He3 that might well have been mined and shipped from the lunar surface. Given the energy costs in accelerating and decelerating the ship in the way you describe, which would run a million people's homes for an afternoon, I personally think the life-support approach would be less. But there's nothing in your figures that wrecks internal consistency with the rest of the setting and cannon backs up efficient fusion power, so I guess the real answer is whatever the GM's imagination demands. biggrin.gif

When your players get back, do us a favour and put us out of our misery about those fucking dragon bones, will you? wink.gif
Steak and Spirits
QUOTE
When your players get back, do us a favour and put us out of our misery about those fucking dragon bones, will you?


The UCAS government has just confirmed that what you thought were Dragon Bones was actually a weather baloon.
eidolon
Oh man. Can we see another "YotC" length/style supplement come from this? It might actually lead me to buy a SR4 book. biggrin.gif
ChicagosFinest
Get the hell out its dragon bones! Just like you UCAS governmental types to hide what you know from the public. When are you going to let us know about area 54 and Roswell New Mexico? Yeah I bet the azzies are going to say something about that one arent they?

biggrin.gif
Steak and Spirits
....

Johnson. We have a problem.

Bring the Neuroneutralizers. And more weather baloon footage.
Crusher Bob
You can take a look at Atomic Rockets for the description of a lot of proposed spacecraft drives.

There's also the possible reactionless drive
hyzmarca
QUOTE (Crusher Bob @ Nov 5 2006, 08:26 PM)
You can take a look at Atomic Rockets for the description of a lot of proposed spacecraft drives.

There's also the possible reactionless drive

Never forget Burnsides Advice: Friends Don't Let Friends Use Reactionless Drives In Their Universes.

This isn't because reactionless drives are unbelievable or infeasible. This is because they give any and every 2-bit suicide bomber the ability to shatter planets with the equivalent of a rowboat.

Edit:But really, if you want to get to Mars fast, just summon a spirit with Movement, Guard, and Innate spell:Levitate, Blood Invoke it, and feed it a few hundred lab rats.

Lets say you've got a 100,000 kg pressurized box without engines (engines are unnecessary in this scheme) and including crew weight. A blood spirit who has been fed 200 white lab rats (6 essence each) will be able to get 600 successes at threshold 500 on a force 1188 (1200-12) spell for a movement rate of 118,800 m/ct or 39,600m/s. Add Movement to this and the vessel will have a movement rate of of 47,044,800m/s. It takes 12 boxes of damage from the background count but shrgs them off with several hundred resistance successes.


The trip between Earth and Mars takes less than half an hour without any fuel costs (aside from the lab rats and the initial sapient sacrifice).

The Guard power even eliminates the need for a box or protective gear. The levitation spells and movement power could be applied to the astronauts individually and the guard power will take care of little details like oxygen and deadly radiation.
Since an astronaut in comfortable street clothes is likely to weigh less than 200 kilograms they can increase their travel speed to 282,286,800m/s

5 more rats will let them break lightspeed.

Edit2: Really, forget about manned missions. There could be tours leaving every 15 minutes. No hassle, no fuss, and no long lines. Mommy and Daddy Wageslave should have no trouble taking little Timmy on one of Aztechnology's Mars tours. With no safety gear to worry about, no annoying airport security, and a round-trip travel time of less than a second, there is a killing to be made in Mars tourism. The best part is that nothing can possibly go wrong unless the summoner dies (or a tour party is attacked by a similarly imbued blood spirit)
Digital Heroin
QUOTE (ChicagosFinest)
Get the hell out its dragon bones! Just like you UCAS governmental types to hide what you know from the public. When are you going to let us know about area 54 and Roswell New Mexico? Yeah I bet the azzies are going to say something about that one arent they?

biggrin.gif

The official stance of this office is that the dragon bones, dragons themselves, Elvis, the entire town of Roswell, and Tina Turner's legs are in fact swamp gas.

You may carry on with your life now citizen, and sleep well.
Demerzel
First of all by Fuel I mean reaction mass, it could be water or spotted owles, all it has to have is mass.

Well claiming that you could use some sort of super particle accellerator to create the velocity for the reaction mass is inconsistant with the technology presented in the current game usiverse. If you could accellerate reaction mass to velocities high enough to create the kind of accelleration you're recomending with mere hundreds of kilograms of mass you'd also be able to put that kind of technology into propelling projectiles from guns and we don't see anything like that anywhere else in the SR world.

There are two keys to thrust. Thrust from a action reaction no matter how the power comes follows:

Thrust = -u * dm/dt

Where thrust is positive because dm/dt is negative (The rocket is losing mass), and u is the velocity of the propellant (Like I said, it could be water or dead mob capos.)

So if you want to reduce dm/dt you have to increase u. You say that we can write in a future tech that allows us to do whatever we like with u, but I argue that if you can make a interplanitary engine that can create those kind of propellant velocities it would have ramifications that are visible in the terestrial technologies and that does not appear in SR as we see it.
Jack Kain
You'd spin the crew comartment of the ship. The crew's quarters and recreation section could be in a cylinder that would spin at about 2 rpm (possibly more if the crew had bio/cyberware instailed to fight off the effects of Coriolis.) This would generate some gravity. At least a an exercise room spining at a higher rate say 6 or 7 rpm.

If you could some how ignore the effects of Coriolis you could duplicate earth's gravity on a ship 18 meters wide by spining at about 14 rpm. (that would leave a normal unmodified human on the "ground" puking)


The center of the ship which would still be weightless would contain much of the important power equipment and life support, as well as the engine room at the back and the bridge towards the front.
Demerzel
Also le t me give you an idea of the unreasonableness of assuming a reaction mass velocity from a plasma engine having any speed you like:

The temperature at the core of the sun is: 1.36E+07 K(wiki)

The average energy of a particle based on temperature is 3/2 K T

Where K is boltzman's constant: K = 1.3807E-23 J / K

So the average energy of a particle in a plasma as hot as the core sun is: 2.817E-16 J

A proton has mass near enough to 1u = 1.66054E-27 kg.

E = mv^2 non relativistic, so v = sqrt(E/m) in this case v = 4.12E+05 m/s.

Thrust = -u dm/dt, and we assume we bottle the sun then to get a 100,000 kg ship to accelerate at 9.8 m/s then dm/dt would have to be 2.38 kg/second.

For 345600 seconds going two days there and two back?

Granted as the ship loses mass you can decrease dm/dt and still get the same acceleration. But if you want to do it on a mere 1000 kg of reaction mass? And I would still argue that the core of the sun is not a feasable estimate for the core of a plasma jet.
FrankTrollman
QUOTE
Well claiming that you could use some sort of super particle accellerator to create the velocity for the reaction mass is inconsistant with the technology presented in the current game usiverse. If you could accellerate reaction mass to velocities high enough to create the kind of accelleration you're recomending with mere hundreds of kilograms of mass you'd also be able to put that kind of technology into propelling projectiles from guns and we don't see anything like that anywhere else in the SR world.


Shadowrun Thor Shots are mass driver based, you actually do have large scale space-based hyperaccelerators that are used in war. Shadowrun's game universe already has that and has for some time (they were first discussed I think in Paradise: Lost).

You don't have it in hand held weapons, but that's not particularly germaine to a discussion about a 100 tonne object with a fusion reactor that is in space.

QUOTE
The temperature at the core of the sun is: 1.36E+07 K(wiki)

The average energy of a particle based on temperature is 3/2 K T

Where K is boltzman's constant: K = 1.3807E-23 J / K


Wow. That's amazingly not meaningful to this discussion. In fact, you've just proved that rocketry is impossible because the temperature of the exhaust of the space shuttle is only 3600 degrees Kelvin. That means that by your calculations it would require the launching of some 23 tonnes of fuel every second just to keep the space shuttle stationary.

And it would - if hypothetically the exhaust didn't also have a directional kinetic push in addition to its raw heat derived particle speed.

But it does have that, which is where the vast majority of the impetus comes from. You aren't just heating things up and then opening a door for plasma to osmosis out of - you're charging it up with directional kinetic energy and then firing it backwards.

-Frank
Vaevictis
QUOTE (Demerzel)
Thrust = -u * dm/dt

Well hell, in that case, let's burn off a kilo of mass in a Plank Time! Problem solved!

(I keed, I keeed!)
Draconis
QUOTE (hyzmarca @ Nov 6 2006, 02:32 AM)
QUOTE (Crusher Bob @ Nov 5 2006, 08:26 PM)
You can take a look at Atomic Rockets for the description of a lot of proposed spacecraft drives.

There's also the possible reactionless drive

Never forget Burnsides Advice: Friends Don't Let Friends Use Reactionless Drives In Their Universes.

This isn't because reactionless drives are unbelievable or infeasible. This is because they give any and every 2-bit suicide bomber the ability to shatter planets with the equivalent of a rowboat.

Edit:But really, if you want to get to Mars fast, just summon a spirit with Movement, Guard, and Innate spell:Levitate, Blood Invoke it, and feed it a few hundred lab rats.

Lets say you've got a 100,000 kg pressurized box without engines (engines are unnecessary in this scheme) and including crew weight. A blood spirit who has been fed 200 white lab rats (6 essence each) will be able to get 600 successes at threshold 500 on a force 1188 (1200-12) spell for a movement rate of 118,800 m/ct or 39,600m/s. Add Movement to this and the vessel will have a movement rate of of 47,044,800m/s. It takes 12 boxes of damage from the background count but shrgs them off with several hundred resistance successes.


The trip between Earth and Mars takes less than half an hour without any fuel costs (aside from the lab rats and the initial sapient sacrifice).

The Guard power even eliminates the need for a box or protective gear. The levitation spells and movement power could be applied to the astronauts individually and the guard power will take care of little details like oxygen and deadly radiation.
Since an astronaut in comfortable street clothes is likely to weigh less than 200 kilograms they can increase their travel speed to 282,286,800m/s

5 more rats will let them break lightspeed.

Edit2: Really, forget about manned missions. There could be tours leaving every 15 minutes. No hassle, no fuss, and no long lines. Mommy and Daddy Wageslave should have no trouble taking little Timmy on one of Aztechnology's Mars tours. With no safety gear to worry about, no annoying airport security, and a round-trip travel time of less than a second, there is a killing to be made in Mars tourism. The best part is that nothing can possibly go wrong unless the summoner dies (or a tour party is attacked by a similarly imbued blood spirit)

Very funny sleepy.gif . You and I both know they're closing the blood spirit loophole that never should have been created in the first place.

Oh and we're not launching from groundside on Earth, that's just nuts. We're going up the well to meet the ship and then doing orbit to orbit.
But first, training in Antartica! Those suit warmers better damn well work. I hate the cold. smile.gif

This is the reason I play Shadowrun. Tres cool epic runs like this.
ChicagosFinest
Ahh so it is the dragon who plans to go retreive the dragon bones and he had his S-K space facilities to do the training. Now I understand why target wastelands was put into print.

Lightbright you crafty and wacky elf I should have saw that one comming when the ruins in antartica were mentioned along with the name of Loffy and lightbright but thats a big hole of a connection to make but now it makes sense.

So then when mars gets as close as it can get to earth were going to have another space race campain (like year of the commet). I scan you and dig it.
2bit
and bringing the topic to SR products again, where can I get information on space related technology, property, and resources? (Satellites, habitats, moon bases, terrestrial lift complexes...) Is it all in Target: Wastelands?
FrankTrollman
QUOTE (2bit)
and bringing the topic to SR products again, where can I get information on space related technology, property, and resources? (Satellites, habitats, moon bases, terrestrial lift complexes...) Is it all in Target: Wastelands?

Pretty much, though there is also some in SotA: 2064 (Mars Probe successful) and Street Magic.

The stable orbital platforms have weak manaspheres generated by specially engineered plants. This allows you to use magic there without explosive decompression. Mobile units such as asteroid miners and transports, don't stick around in one area long enough for that to happen.

-Frank
Demerzel
QUOTE (Frank)
Wow. That's amazingly not meaningful to this discussion. In fact, you've just proved that rocketry is impossible because the temperature of the exhaust of the space shuttle is only 3600 degrees Kelvin. That means that by your calculations it would require the launching of some 23 tonnes of fuel every second just to keep the space shuttle stationary.


Well actually if you follow my calculations the space shuttle would need about 2,110 kg/s dm/dt in order to maintain stationaryÖ (If exaust is 3,600K)

If you want 3g of acceleration at launch you use 6,330 kg/s

In fact the space shuttle uses closer to 10,000 kg/s of reaction mass at launch. Yes, it uses something on the order of a million kg of fuel in the first two minutes.

So Iíd say not too bad for a back of the envelope calculation. Not to mention the process errs on the conservative side.

QUOTE (Frank)
And it would - if hypothetically the exhaust didn't also have a directional kinetic push in addition to its raw heat derived particle speed.


What the heck do you mean by directional kinetic push?

If you mean that we will first heat your plasma, then run it thorough some sort of accelerator? A sort of spaceship sized linear accelerator? I still contend that the world of SR does not indicate that this type technology.

Now if you want a space race it would be way more reasonable to assume a smaller ship than would be necessary to contain the amount of reaction mass youíre talking about. If you want constant acceleration accept something much more like a few percent of one gravity.

While youíre trying to boost a ridiculous amount of reaction mass into space someone else will send up a small ship and accelerate at a constant a few percent of what youíre proposing and make it in a couple months.

Basically, 2 days is ridiculous, it would be way more acceptable to assume a couple months, and that the medical technology of the Cyber world of SR would make it reasonable for the astronauts to make the trip and not be atrophied weaklings with heart failure at the end.

And donít forget all this is assuming that you donít land on Mars and want to boost off again, or somehow stay long enough to prepare sufficient reaction mass to take off again.
ChicagosFinest
most of it yeah. Wake of the commet is probably another good one to look into but mainly target wastelands
FrankTrollman
QUOTE
In fact the space shuttle uses closer to 10,000 kg/s of reaction mass at launch. Yes, it uses something on the order of a million kg of fuel in the first two minutes.


Yes. And the Space Shuttle is over 2 million kilograms, not 100,000. So your calculations would call for it requiring over 120,000 kg per second.

You're off by an order of magnitude, and we haven't even taken into account that this is happening in-atmosphere, where friction is a big problem.

-Frank
Demerzel
Okay, you want it line by line:

K = 1.38E-23 J/K
T = 3600 K
E = (3/2)KT = 7.46E-20 J
1u = 1.66E-27 kg

KE = 1/2 m v^2 = 3/2 KT

v = sqrt(3KT/m)=9467m/s

Thrust (Force = Mass * Accelleration) = 2,000,000 kg (Space Shuttle on Platform) * 30 m/s^2 = 60,000,000 N

Thrust = -v * dm/dt

Dm/dt = Thrust / -v = 60,000,000N / 9467m/s = 6331 kg/s

So Iím not off by an order of magnitude, not even close.
Butterblume
Using today's possible technology, it seems sweat deal to launch a several million ton spaceship into earth orbit with less than 5 kilotons of fuel. Especially if you don't particularly care about the environment. Alltough, thinking about it, to bring a similar paylod to orbit would require about a million or more space shuttle starts, which also wouldn't be very easy on the environment...

(source:Project Orion)
FrankTrollman
Sorry Demerzel, I was way too generous with your calculations.

According to your calcs, a 100 tonne object would need over 2 kilos of ejecta per second per G at 10^7 Kelvin, with a linear relationship with temperature.

The ejecta of the space shuttle is less than 1/1000th that temperature, so it would need 1000 times that per G of acceleration every second. So our 100 tonne object would need to fire over 2 tonnes every second for 1 G.

Let's bring this into the general case. That's 2% of mass per second per G.

A Space Shuttle Launch lasts eight and a half minutes (510 seconds) and has about 3 Gs of acceleration. That would be 510 seconds losing 6% of total mass each second.

So the payload, as a percentage of the original load + fuel, would therefore be .94^510 - or approximately 1 gram of shuttle for every 50 million tonnes of fuel.

Congratulations, you just disproved rocketry. :rolleyes:

I'm going to stop checking your math because it's obviously wrong.

-Frank
ChicagosFinest
I think someone just got served
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