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Space Time Travel

08/06/2012 10:22 AM

Hi All,

This is time it takes to travel a distance i Space, Not Space Time Travel as with Doctor Who.


More math stuff here. Ya know for someone that hated math in school I play with it a lot now, UG!

Anyway the question is. When in space, and away from the gravitational effects of the Earth. What rate of acceleration is needed to end up feeling as if there is 1 G of force on the Astronaut?

Would that freefall proverbial 32 feet per second per second be the number here also?

In other words what rate of acceleration, is needed to feel a constant never ending force of 1 G?

Now this is the even more interesting part.

I know we do not have right now any propulsion systems that are capable of doing this. But if we were to it would cure soo many problems. With space travels.

Say we did have a propulsion system that is capable of making this 1 G of force for as long as we want it to. Several things come to mind.

Mainly the removal of the problems physically that happen to the astronauts in long duration flights loss of muscle and bone mass for the first couple.

The next is the time of the trip. This system would have to shorten the trip GREATLY I would think.

Anyone care to try to make a calculation on this?

Say both to the moon as well as to mars.

Now current technology take 3 days to go to the moon and 8 months to go to mars. But 99% of the trip is under 0 or near 0 gravity or G forces.

Now the question is, again if we were able to make a propulsion system of doing this, what would happen,?

We launch Yeah LOTS of G forces at first but once left the Earths Gravitational forces and onto either the moon or mars, we now are accelerating at 1 G force.

I would assume at close to the 1/2 way point we would turn the ship around and again keep running the engines, but again with 1 G forces worth of thrust so to start to slow the ship down now.

The questions are

On both trips to the moon as well as to mars, I would assume max speed would be at that 1/2 way point,, how fast would they be traveling?

And then the big one how long would the trip now take?

Joe

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Anonymous Poster #1
#1

Re: Space Time Travel

08/06/2012 11:03 AM
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#2

Re: Space Time Travel

08/06/2012 11:11 AM

<...what rate of acceleration, is needed to feel a constant never ending force of 1 G...>

About 32 feet per second per second, or 9.81 metres per second per second, would do the job nicely. Bear in mind that:

  • Mars' surface gravitational acceleration is less than the above.
  • The moon's surface gravitational acceleration is less than the above.
  • There is a gravity "col" or "saddle" that a vehicle must overcome to approach another planet or moon, otherwise it cannot be captured by its gravitational field. The col is closer to the body of lower mass, therefore "halfway" is not applicable.
  • The reason constant acceleration/deceleration is not used is that it is heavy on propellant, and getting all that propellant out of the gravity well that is the Earth is not practicable. It is easier/cheaper/more practicable to use a Hohmann Transfer Orbit.

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#3

Re: Space Time Travel

08/06/2012 11:23 AM

Calculating the speed at the half-way point to the moon is a relatively simple exercise in calculus. Perhaps someone will throw in their 3 cents worth (inflation!).

Probably the most significant reason for not having acceleration (1g or some smaller value) during spaceflight is due to the consumption of fuel. Generating acceleration WILL take fuel to produce, and getting fuel into orbit takes more fuel during launch, and taking more fuel during launch takes a larger launch vehicle, and ....

You can quickly see that adding a requirement for acceleration to a space vehicle greatly increases the complexity of every aspect of a space flight, and this adds to its risk as well. One day, perhaps, we will be more able to add acceleration but this is not too likely in the near-term future.

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#4

Re: Space Time Travel

08/06/2012 12:12 PM

Yes I know all about the slingshot stuff. As well as the problem with propellants and their weight. I did mention these problems in the question.

Well not the slingshot, but of course with the slingshot you still have the bad effects of zero G on the passengers. but that no such magic propellant exists yet.

But the question is.

If there indeed was a new magic propellant that would allow such a flight to happen, what speeds and timelines would have happened?

Thanks.

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#5
In reply to #4

Re: Space Time Travel

08/06/2012 12:16 PM

That is a relatively simple question to answer. What answer have you come up with?

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#6
In reply to #4

Re: Space Time Travel

08/06/2012 12:56 PM

Well we could make propellant on our Moon Base, if we had a moon base...At it's closest point Mars is about 55 million km it would take about 42 hrs.....Your top speed would be a little more than 1.6 million mph...

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#7
In reply to #6

Re: Space Time Travel

08/06/2012 1:13 PM

Wow Really? That Short?

Wow!

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#9
In reply to #7

Re: Space Time Travel

08/06/2012 1:37 PM

Actually, not quite. It would be a little longer due to Mars and Earth moving in their orbits, but not far off.

That is also the optimum shortest distance between Earth and Mars and those conditions do not happen all that often. The current trip to Mars for Curiosity was about 250,000,000 kilometers.

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#8

Re: Space Time Travel

08/06/2012 1:32 PM

The calculations are very simple.

a = Δv/Δt = (Vfinal - Vinitial) / (Tfinal - Tinitial)

If the initial velocity and time are taken to be zero, the equation simplifies to:

a = v / t

You can rearrange the equation to solve for any one to the terms you want. If you want to solve for distance, then the following is true:

d = 1/2 v × t

The issue with what you are proposing is simply a matter of energy. For a chemical rocket most of the mass of the rocket is fuel. To generate enough thrust for 247 million kilometers of flight is simply prohibitive.

Chemical rockets have a limit to velocity based on the exhaust speed of the propellant. The Tsiolkovsky rocket equation will tell you why. Obviously some other propulsion is required and the only propulsion system that might have a shot at generating that kind of acceleration would be nuclear. No such systems even exist yet.

For a trip to Mars (250 million kilometers) you would need enough thrust for almost 3.75 days (both acceleration and deceleration times) and your maximum velocity would be just over 1,500 km/s.

Your exhaust velocity would need to be even higher to provide the 1 G of thrust. So, you need an extremely powerful engine.

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#12
In reply to #8

Re: Space Time Travel

08/06/2012 3:28 PM

??

Chemical rockets have a limit to velocity based on the exhaust speed of the propellant. The Tsiolkovsky rocket equation will tell you why. Obviously some other propulsion is required and the only propulsion system that might have a shot at generating that kind of acceleration would be nuclear. No such systems even exist yet.

??

Umm, almost every rocket we use now makes many many times 1 G force now,

So this statement confused.

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#14
In reply to #12

Re: Space Time Travel

08/06/2012 4:22 PM

Delta-v (rocket equation)
Main article: Tsiolkovsky rocket equation

The delta-v capacity of a rocket is the theoretical total change in velocity that a rocket can achieve without any external interference (without air drag or gravity or other forces).

When is constant, the delta-v that a rocket vehicle can provide can be calculated from the Tsiolkovsky rocket equation:[103]

where:

is the initial total mass, including propellant, in kg (or lb) is the final total mass in kg (or lb) is the effective exhaust velocity in m/s or (ft/s) is the delta-v in m/s (or ft/s)

When launched from the Earth practical delta-v's for a single rockets carrying payloads can be a few km/s. Some theoretical designs have rockets with delta-v's over 9 km/s.

The required delta-v can also be calculated for a particular manoeuvre; for example the delta-v to launch from the surface of the Earth to Low earth orbit is about 9.7 km/s, which leaves the vehicle with a sideways speed of about 7.8 km/s at an altitude of around 200 km. In this manoeuvre about 1.9 km/s is lost in air drag,gravity drag and gaining altitude.

The ratio is sometimes called the mass ratio.

http://en.wikipedia.org/wiki/Rocket

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#16
In reply to #12

Re: Space Time Travel

08/06/2012 5:14 PM

I need to make a correction to what I said. There is no theoretical limit to the velocity of a chemical rocket, but there is a practical limit. That limit is the amount of propellant you need to achieve a constant acceleration for a duration long enough to get through a Mars or even a lunar burn.

It is a "Catch 22" situation. To achieve a very long burn time you need lots of propellant. However, the more propellant you carry, the more energy you need to move that huge mass, so you end up exhausting all of your fuel just to get that huge mass going.

Look at the Space Shuttle. The amount of propellant carried by the external tank is 730,000 kg (about 10 times the mass of the Shuttle Orbiter). There is also 504,000 kg of solid propellant. That is all gone in about 8 minutes.

To sustain a one-way trip to Mars at that burn rate would require 630 times that amount of fuel if the additional fuel had zero mass. However, since the mass is also 630 times, you need to burn a whole lot more fuel just to get to 1 G acceleration, but it becomes an impossible feat because we simply do not have enough engine power to ever lift the huge mass of fuel needed and sustain the burn for days. It is a vicious cycle; you need more and more fuel to move the fuel you need to keep the rocket going.

Now, here is where exhaust velocity comes in. The energy derived from a chemical rocket (or any other rocket that has thrust) is KE = 1/2mv^2, where KE = energy, m = mass of the propellant, v = the velocity of that propellant out of the exhaust nozzle.

The cue here is the velocity is squared in the equation, so doubling the velocity of the exhaust yields a geometric expansion of the energy produced.

A solid rocket booster produces 2.7 km/s exhaust velocity. If we arbitrarily assign a fuel mass of 1000 kg, we get about 3.6E9 kg•m/s^2.

Double the exhaust velocity and we get 14.6E9 kg•m/s^2. That is a lot more bang for the buck. The solution is getting ultra high exhaust velocities so we can keep the overall fuel mass low. Chemical rockets just can't do that because the maximum exhaust velocity is so low (relatively speaking).

You need exotic propulsion systems that require low masses of fuel so that we do not need Herculean forces to move the space craft, but generate very, very high exhaust velocities so as to take advantage of the square of the velocity of the exhaust.

The bottom line is there is no current technology or even technology on the horizon this century that will provide the kind of thrust you propose (9.8 m/s^2) for the durations needed to get to the Moon, let alone Mars.

The only one that can do that is Hollywood.

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#17
In reply to #16

Re: Space Time Travel

08/06/2012 6:49 PM

"The only one that can do that is Hollywood."

Up till now.

The transistor was only invented in the 1920's and not practical till '47.

Look where we've gone from there.

We did just land a 1 ton SUV on Mars.

Who knows???

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#18
In reply to #17

Re: Space Time Travel

08/06/2012 7:17 PM

I would like to think so, but the snail's pace we are making into space says otherwise.

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#22
In reply to #12

Re: Space Time Travel

08/07/2012 7:32 AM

It's easy (relatively) to generate massive acceleration while traveling at low speeds. Acceleration is a function defined by the inverse relationship of vehicle velocity to exhaust gas velocity. While the vehicle is slow, and exhaust gas velocity is at max, the acceleration is also at max, but as vehicle velocity increases toward max, it also increases toward exhaust gas velocity, with the result that as the delta between the two decreases, so does the acceleration that is available.

Hence, we can build aircraft (the F-16, in the US) which are capable of such massive acceleration under the thrust of their engines alone (no catapult launch, since they aren't shipboard capable) that they can literally accelerate, straight up. But, realizing that the limit of available altitude is also affected by thinning of air (their engines are air-breathing jet engines, as opposed to oxidizing rocket engines), that capability is also limited by the fact that as they accelerate at multiple g-s, they also approach their exhaust gas velocity limits.

Thrust producing chemical engines, regardless of design, fuel, or any other factor, will always have an upper limit driven by exhaust gas velocity. Eliminate that, and other factors will weigh heavier, and possibly up the vehicle velocity limit. But without eliminating that consideration, we're still stuck at the relatively slow velocities currently available.

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#23
In reply to #22

Re: Space Time Travel

08/07/2012 8:19 AM

Very good points about exhaust velocity versus acceleration.

The F-16 really doesn't have much acceleration. At takeoff weight the thrust to weight ratio is about 1, so a true vertical climb is pretty slow (almost nil) without the advantage of having significant forward airspeed before initiating the climb.

There is a good video that Top Gear did that demonstrated the takeoff acceleration of a Eurofighter fighter jet (thrust to weight ratio of 1.25:1) compared to a Bugatti Veyron.

The Veyron covered 188 mph in 18 seconds, which is an average acceleration of 4.67 m/s^2, which is less than 1/2 G. Even the zero to 100 time is less than 1 G (7.8 m/s^2) and kicked the Eurofighter's butt, at first. However, the jet has the advantage of more power and in the end builds up a lot more speed.

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#24
In reply to #23

Re: Space Time Travel

08/07/2012 8:38 AM

K. Thanks. I never looked at specific T-W ratio for an F-16, and confess that I was basing example on word of mouth from friends who fly (or flew) it. And it's probable that, like most macho studly people who fly, they think it (or at least are willing to have us think it) to be the fastest, most powerful, tail-kickingest airplane in the world.

I am shamed. As an engineer, I should have looked it up, instead of spouting about what I haven't seen/verified/checked myself.

Anyway, thanks for the gentle flogging. I needed that. And the accurate data. I trust. I still didn't check.

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#25
In reply to #24

Re: Space Time Travel

08/07/2012 8:52 AM

Not a big deal. Aircraft jet engines just do not have a lot G kick, but they can develop a lot of velocity given time.

Perhaps the exception might be the SR-71, which has a very high thrust to weight ratio. Amazing technology for something out of the 1950s.

However, your point about the delta between exhaust velocity and vehicle velocity when vehicle velocity becomes close to the exhaust velocity was an excellent point. There simply isn't enough oomph to generate meaningful acceleration at that point.

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#26
In reply to #25

Re: Space Time Travel

08/07/2012 9:28 AM

Very much similar, and for very similar reasons, to the limitations on a gas turbine engine used for direct torque output in a land vehicle. At zero turbine wheel speed, but maximum internal pressure/gas jet velocity, you get maximum torque out. But as the turbine wheel approaches it's max rotational velocity, the torque drops off in a linear fashion, to near zero with the result that turbine horsepower out is a linear, fairly flat curve over the entire RPM range (since HP is directly related to Torque X RPM).

Too bad the Granatelli's lost that turbine bearing at Indie.

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#10

Re: Space Time Travel

08/06/2012 2:30 PM

Maybe a Higgs Bosun's chair would work?

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#11
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Re: Space Time Travel

08/06/2012 3:16 PM

The God Stool.

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#13

Re: Space Time Travel

08/06/2012 3:47 PM

If you hollowed out a big rock and put in some form of high heat chamber, say a nuclear fusion plant and threw rock into the chamber where it vaporized and squirted out of the back, propelling the rocket. The ship would gradually lose mass material as it was consumed as propellant, material because Relativity says it gains mass with velocity.

So what velocity would the propellant need to accelerate the ship to say, C/2 while only expending 50% of it's material?

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#15
In reply to #13

Re: Space Time Travel

08/06/2012 4:36 PM

That's how a dilithium-powered anti-matter warp drive works.

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#19

Re: Space Time Travel

08/07/2012 1:24 AM

During the cold war, the US developed a nuclear powered missile and it was functional, but never used.At the time it was designed to be an ICBM and deliver a nuclear warhead as well.I remember the nuclear reactor was the heat source, but don't remember the gas that was expelled as a propellent.

Perhaps if this info is still available, it may still be viable as a power source for a rocket.

Anybody want to dig that up?

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#20

Re: Space Time Travel

08/07/2012 2:21 AM

Me brain hurts.

Bazzer

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#21

Re: Space Time Travel

08/07/2012 2:52 AM

thank you...nice post..

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#27

Re: Space Time Travel

08/07/2012 9:51 AM

Some have scratched the surface of this point, but almost half of the fuel would be needed to decellerate the vehicle (presumably also at 1G) for orbit or entry to Mars atmospere. So where does that put the timeframe? Is it also intended to return to Earth?

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#29
In reply to #27

Re: Space Time Travel

08/07/2012 10:41 AM

No. The first flight (B Ark) is only for politicians, telephone sanitizers, and attorneys.

The rest of us will follow at a later date.

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#32
In reply to #29

Re: Space Time Travel

08/07/2012 10:57 AM

If we can send all of them there, why would we need to leave? And why would we want to go wherever they are, anyway?

I'd prefer to get away from it them all, if I had a choice.

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#34
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Re: Space Time Travel

08/07/2012 11:02 AM

Ah, you need to read more. For instance, The Hitchhiker's Guide to the Galaxy would be a good start. :)

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#36
In reply to #34

Re: Space Time Travel

08/07/2012 11:11 AM

I did that once. Started it, I mean. Just couldn't get into it. Not enough gore, I guess.

Or something.

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#37
In reply to #36

Re: Space Time Travel

08/07/2012 11:48 AM

Do a search for "The B Ark".

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#38
In reply to #37

Re: Space Time Travel

08/07/2012 12:11 PM

Ah. Done, and mightily enlightened. So, WHY was Ford Prefect there? And how did HE get back?

OK, never mind. My wife always tells me to read it myself (or watch it, or listen to it, or ...) before asking questions.

I mean, I read an average of 150 books a year, and hate watching TV or movies because their plot development is too slow. But I just HATE coming into the middle of it and not being able to get answers to the questions that follow.

But I'll be good, and read it myself.

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#40
In reply to #38

Re: Space Time Travel

08/07/2012 12:32 PM

Almost every engineer has read that book. You will love it.

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#42
In reply to #40

Re: Space Time Travel

08/07/2012 12:53 PM

Yeah. But as an engineer who learned by doing, as opposed to learning by college and THEN doing, I "escaped" (quotes, because it might not have been an escape) a lot of the fun my engineering brethren took part in. Including reading that one.

But you may be right. If it isn't too painfully silly (I AM much older now, I suspect, than most engineers are when they read that) I probably will have to revisit the old, and underexperienced, joys.

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#43
In reply to #42

Re: Space Time Travel

08/07/2012 1:02 PM

It is full of irony. Just don't wear a magnet.

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#44
In reply to #43

Re: Space Time Travel

08/07/2012 1:08 PM

Now THAT was low! I mean, my punny-bone IS rusty, but ... well, that was just the bottom of the well.

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#45
In reply to #43

Re: Space Time Travel

08/07/2012 1:09 PM

Or, as my daughter would say, "Well played".

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#46
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Re: Space Time Travel

08/07/2012 1:16 PM

:)

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#28

Re: Space Time Travel

08/07/2012 10:20 AM

Plus Jet Engine Thrust and Rocket Motor thrust are different.

A Jet engine even if it had a source of air to run on, would provide zero or very little thrust in space. Whereas a Rcket motor will. because of the nature of how the thrust of expanding gasses is used. a Rockets thrust is mainly produced by pushing on the specially shaped rocket nozzle. NOT by pushing on the air behind the motor.

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#30
In reply to #28

Re: Space Time Travel

08/07/2012 10:55 AM

Hmm. Interesting point. And I WOULD (though I can see the error, now that you name it, just considering the relative shapes of both the jet and the rocket nozzles) have made that mistake. Thanks for pointing it out.

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#31
In reply to #28

Re: Space Time Travel

08/07/2012 10:56 AM

That is not quite right.

You are not pushing on anything with a jet, you expelling fuel and air.

The formula for net thrust for a jet engine is:

F = (Mair + Mfuel)•Vexhaust - Mair•V

Where:
Mair = mass rate of the air flow through the engine
Mfuel = mass rate of fuel entering the engine
Vexhaust = Velocity of exhaust plume
V = Velocity of air intake (aircraft true airspeed)

Nowhere in that equation is there an expression for pushing against anything (air or otherwise). The thrust generated is a function of the quantity of mass ejected rearward and the square of the velocity of that mass (Ke = 1/2m•v^2).

For example, if you are in a still lake on a boat full of bricks and you start hurling those bricks behind into the lake the boat will move forward as you toss those bricks back.

The boat moves forward not because the bricks push on the air or the water, but by obeying Newton's Laws of motion.

Furthermore, the jet engine and the rocket nozzle both eject mass in the same direction. The function of each is to eject mass as much as possible directly opposite the direction of travel to maximize thrust. If you think about it, you get much better thrust throwing those bricks directly opposite of your desired travel than you would throwing them at 45° angles from due aft. Simple vector math demonstrates that.

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#33
In reply to #31

Re: Space Time Travel

08/07/2012 11:00 AM

Sooo, the rocket's thrust is NOT due to pushing against it's nozzle, either?

I mean, that makes sense, because the rocket, too, has to obey the third law. But the nozzles are certainly different in design and shape, and the relative shape differences make his point look pretty good, also.

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#35
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Re: Space Time Travel

08/07/2012 11:04 AM

All nozzles shape the exhaust plume so that it is as much as a straight line pointing aft as possible.

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#39

Re: Space Time Travel

08/07/2012 12:28 PM

I was given to understand that once you reach space and are free of Earths gravity, you can shut down the propulsion engines and your speed would remain the same, so why couldn't you start the engine again in bursts to keep accelerating something like firing a big gun?

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#41
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Re: Space Time Travel

08/07/2012 12:37 PM

Yes, you can coast, but it is no different when driving a car on a flat freeway. When holding a steady speed you feel no acceleration.

To get acceleration you must apply throttle. The moment you stop applying throttle you return to zero acceleration and zero G inside the cabin.

Needless to say, if you repeated that goosing of the throttle once every second you would have a very bumpy ride. You would not want to eat dinner like that.

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#52
In reply to #41

Re: Space Time Travel

08/08/2012 3:14 AM

Are you saying that when Capt Kirk says "ahead warp factor 8" every one on board ends up flat against the wall?

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#54
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Re: Space Time Travel

08/08/2012 9:40 AM

Ha!

Well, it's just a TV show, but like anything on Star Trek they tend to try to support it with a theory.

For warp drive there is no specific impulse to the ship or its contents. It is the folding of space (warping) that takes place. Essentially, nothing can travel faster than light. This does not apply to space (and the hyper inflation of space during the Big Bang supports this), so the theory is that you move space around you. Such is the power of dilithium. :)

For the ship's impulse engines they use the artificial gravity generators to counter the effects of the acceleration or something like that.

When you fall out of a plane you are accelerating due to the force of gravity. In free fall you feel weightless, but you are actually accelerating. The reason you feel weightless is because every atom in your body is being accelerated uniformly at the same magnitude of force.

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#47

Re: Space Time Travel

08/07/2012 6:39 PM

Rather than using the thrust to provide the G force, what if we spun the rocket around it's longitudinal axis like a rifle bullet. Could the centrifugal force generated by spinning substitute for a gravitational force?

It would have the problem not being constant. Zero Gs at the axis and maximum Force at the outer circumference. It may still be useful for the health of any human cargo.

Once the spin is established it should remain reasonably constant and not require the constant effort of the thrust form of artificial gravity.

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#48
In reply to #47

Re: Space Time Travel

08/07/2012 7:13 PM

Looks like a donut, or a tube?

How fast will you need to spin? Spinning Wheels

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#49
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Re: Space Time Travel

08/07/2012 7:20 PM

Yes.

However, when you turn your head to talk to the person next to you, you will throw up.

When I took my first centrifuge ride at NASA I was specifically warned about doing just that. Turning your head while spinning disturbs the vestibular region of the ear and spooks the brain into thinking you are moving in a direction that you are not as compared to what your other senses and eyes tell you.

The result is a bad case of motion sickness!

The fix is to make the centrifuge very large so that it only has to spin at a low angular rate. I don't know what that minimum size is, but I think it is huge and it becomes a mechanical and engineering nightmare to build a spacecraft that incorporates that.

The other problem with spinning is that any redistribution of weight upsets the center of balance of the system, so some form of an active system needs to be used to compensate for people and objects moving within the spinning wheel.

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#50
In reply to #49

Re: Space Time Travel

08/07/2012 8:45 PM

Who are you who are so wise in the ways of science? Or better, what coast is the "space coast", Florida or Texas? If either, how many do you know have lost jobs in the space industry so far?

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#51
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Re: Space Time Travel

08/07/2012 9:49 PM

I am just south of the NASA launch site. This region is called the Space Coast.

I don't work for NASA, although I am in the aerospace business. We were asked by NASA to bid on a project for the Constellation lunar lander, but we turned it down at the last instant (we were just too busy). Good thing, one month later it was cancelled. I hate spinning up for a project, assigning resources, then having the project scrubbed.

I think the total number of NASA employees and their subcontractors let go was about 5,700 at the Kennedy Space Center in Florida. I don't know about any other locations.

Just over half of those employees have found other jobs (as of last month). The rest are either unemployed or retired.

Unfortunately, we may not get to see the same level of activity at NASA again for a long time, possibly not in my lifetime, so those let go are gone for good along with their expertise.

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#53
In reply to #51

Re: Space Time Travel

08/08/2012 8:41 AM

On a related note, do you supposed the landing of Curiosity on Mars will in any way help that out? Cause more hiring? Reutilization/reallocation of existing personnel? Re-hiring some of the retired/RIF'ed talent?

I realize you don't make the decisions, so I'm just looking for an opinion.

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#55
In reply to #53

Re: Space Time Travel

08/08/2012 9:42 AM

It will literally take an act of Congress to do that. They hold the purse strings.

If a majority of people demand that from their representatives, it will happen. Unfortunately, most people get their science thrills from a movie ticket.

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#56
In reply to #55

Re: Space Time Travel

08/09/2012 7:21 AM

Yup. My thinking too. Of course, there are also those who argue that if you don't feed the body, feeding the mind won't matter. But, while that is somewhat true, it's also beside the point. I was fortunate in never growing up so impoverished I had to be hungry, nor, mostly, with people in that circumstance. So, also unfortunately, your argument is lent force by the fact that very few of my "not hungry" classmates were nearly as interested in science, and learning about our world, and just sheer discovery, as I was.

And interestingly, all of my friends who WERE of the same mental bent and curiosity as I was were also NOT brought up on TV and popular entertainment, but on reading, voraciously.

Most of us were the despair of our teachers precisely because we were always reading. We just didn't find our ASSIGNED texts nearly as interesting as the ones we begged or borrowed from more esoteric sources.

But you appear to be right on the point that, no matter what excuses we use to add nobility to our vices, we'd prefer cheap entertainment to more expensive acquisition of knowledge. And that seems to almost always lead to politically controlled purse-strings going to the cheap side of events, and quality brains getting the ax.

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#57
In reply to #56

Re: Space Time Travel

08/09/2012 11:26 AM

The quality brains ares till there. They just need the right nutrients.

If the food consumption habits in the US are any reflection on the knowledge consumption habits of those same denizens then it's not looking good.

Fast food and quick gratification. Sounds like a quality famine to me.

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#58
In reply to #56

Re: Space Time Travel

08/09/2012 5:57 PM

"we'd prefer cheap entertainment to more expensive acquisition of knowledge"

We have a similar problem in Australia. The government is very happy to throw money at sport and elite athletes but very little at research or encouraging excellence in science or engineering.

I guess it has always been that way. If you look back at the Romans with their "Bread and Circus" policy to control the "Roman Mob" and we have TV with the olympics or football and social security

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#59
In reply to #58

Re: Space Time Travel

08/09/2012 6:33 PM

Yeah. The more things (and people, and places, etc. ) change........

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#60
In reply to #58

Re: Space Time Travel

08/09/2012 9:54 PM

Don't get me started.

I've heard some refer to Australians as "Knuckle dragging Neanderthals", which didn't sit well....I just listened.

Bread and circuses...seems to be the way. Democracy in action.

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#61
In reply to #60

Re: Space Time Travel

08/10/2012 7:49 AM

Yep, again. The cost of universal freedom of choice is that some choose stupidly. And when we choose stupid politicians to run it for us, they make the stupid choice to keep bailing out stupid people who made previous stupid choices.

One is left to wonder "If we keep choosing stupid politicians, who is REALLY stupid?"

I'm all for term limits, here in America. But I doubt even that would work very well. And the alternatives, chaos, anarchy, dictatorship, congenital monarchy (sorry, but that's what the "Royals" part of the UK really is), with the obvious result that you either have NO rule, or are ruled by someone over whom you wield NO control, is totally unacceptable.

And distasteful as even WE seem to find it, the fact is, our gun control laws were predicated by people who, while they WERE the power, said words to the effect that, if the electorate is to retain control of the power, it needs the tools (read that as "guns") to do so, when all other means have failed.

Happily, all other means haven't failed, YET, since our revolution and withdrawal from British control.

Woe to us, the day we have to remove the idiots by main force. THEN anarchy will surely reign!!

But it will be vastly more interesting (not to say terrifying) than TV ever is. AND it will have the advantage, at the cost of some of the bright ones, to be sure, of weeding out huge numbers of idiots throughout the country.

Whereupon we MIGHT get back to an interest in science, if only to figure out to keep that debacle from ever happening again.

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