Spaceship Design

[Tarantism]

this thread is really cool. just thought yall should know that.

[Kayra]

How is that supposed to create acceleration towards the sun? The sail works because of the solar wind yes? I dont see any way possible for it to go 'upstream' without outside help

 

Nope, this is not a sail

It is a reflector

It focuses the energy from the sun onto our reactor.. heating the reactant, and creating thrust. (we send the reactant out the back of the ship after we heat it to 2,500 degrees or so.

 

reread my posts "Is antimatter required?"

[Jay-qu]

ohh I understand now :shrug: I can see many troubles with this design, one slight miscalculation and we are all fried!

[Turtle]

How is that supposed to create acceleration towards the sun? The sail works because of the solar wind yes? I dont see any way possible for it to go 'upstream' without outside help

 

Perhaps by tacking & jibing just as sail boats on water do?:shrug: Galaxy Cup Regatta anyone?:hihi:

[Jay-qu]

Perhaps by tacking & jibing just as sail boats on water do?:shrug: Galaxy Cup Regatta anyone?:hihi:

but the solar wind doesnt flow around behind the sail like air does, you would be unable to create a lower pressure on the sun side of the sail.. oh wait you where joking, turtle you old dog you :D

[Turtle]

but the solar wind doesnt flow around behind the sail like air does, you would be unable to create a lower pressure on the sun side of the sail.. oh wait you where joking, turtle you old dog you :hihi:

Mmmmm...I didn't mean to joke, but if it is funny and I don't know it, it is still fine to laugh.:hihi: Is it sure the solar wind does not eddy behind a large solar sail? :shrug: :D Does that even matter in regard to tacking & jibing?

[CraigD]

How is that supposed to create acceleration towards the sun?

A solar sail (light sail) can’t produce an acceleration toward the sun. It can produce an acceleration directly away from the sun, and lower accelerations approaching 90° from directly away from the sun.

I dont see any way possible for it to go 'upstream' without outside help

By light pressure itself, a light sail ship could not. However, such a ship also has mass, so is accelerated by gravity, just as any massive object is. This is “outside help”, but of a kind not only available, but unavoidable.

 

A light sail ship may be made to accelerate toward the sun by reducing its angular velocity around the sun, placing it in a more elliptical “transfer” orbit. When this orbit approaches the desired distance from the sun, the sail is used to increase its angular velocity, placing it in a more circular orbit at that distance.

 

If the sail is used to reduce the ship’s angular velocity to zero, then turned or retracted to produce no acceleration, the ship will fall directly toward the sun.

 

Solar sail ships can take advantage of planets and moons for “gravity assist” acceleration, just as conventional rocket ships do.

 

The sail works because of the solar wind yes?

No.

 

In principle, such a sail could be designed, but to date, most solar sails designs don’t “catch” solar wind protons and heavier nuclei sufficiently to gain much force from them. Instead, they gain their force from the very slight “pressure” due to reflecting photons.

 

Analogies relating light sails in outer space to wind sails on boats floating of bodies of water on Earth are inexact. Light doesn’t flow in a laminar way over light sails, and there’s no equivalent of a sailboat’s hull an keel’s “grip” on the water. However, the best analogy I can think of is: light sail ship is to sail boat as light is to wind as gravity is to water pressure.

[Kayra]

ohh I understand now :shrug: I can see many troubles with this design, one slight miscalculation and we are all fried!

 

That was the reason for sending the energy out from the sun in a 1 KM wide beam. Nothing so concentrated that it would cause problems.

 

The only danger is at the point of focusing the energy, and i suppose that might have it's risks.

 

Most events would likely cause the reflector to lose shape and no more concentrated sunshine.

 

The amount of power that I am beaming is ridiculously large for our needs as well. Might want to beam most of that to earth, and releay what is needed to the spaceship.

 

 

The 4 updraft towers should be able to generate a combined power of at least 400 Mghr of power.

[Jay-qu]

so how do you get around the fact that something in a closer orbit to the sun will have to orbit faster, so at times it will be inaccesible to our ship? multiple beaming towers?

[Kayra]

so how do you get around the fact that something in a closer orbit to the sun will have to orbit faster, so at times it will be inaccesible to our ship? multiple beaming towers?

 

Good question :QuestionM

 

Actually, there is very little inside the orbit of mercury (where I suggested the collector be placed)

 

Since the device is in a polar orbit, it can be set to always have an eyeball on the ship. (imagine looking at the sun, and seeing the collector circling around the outside edge of it.)

[Jay-qu]

ahh now that is a good idea :QuestionM eccentric orbit

 

as for the big scoop that collects particals from the vacuum of space - I hear the average particle density is 10^-3 particles per cm cubed, but this sounds wrong - because then even if you had a scoop of cross-sectional area of 100m^2, would only take in 9.6x10^-7 between here and pluto... am I missing something?

[GAHD]

You would need a minimum of 6 such satilites in opposite orbits (2 in each axis) if my geometry is up to par, depends on where you were in the other axies vs where it is the sun could obscure it. so 6 smaller ones where 3-4 could focus at oncewould seem to be a better system. They'd need a lot of refueling though.

[Kayra]

You would need a minimum of 6 such satilites in opposite orbits (2 in each axis) if my geometry is up to par, depends on where you were in the other axies vs where it is the sun could obscure it. so 6 smaller ones where 3-4 could focus at oncewould seem to be a better system. They'd need a lot of refueling though.

 

More headaches is it? (cracks a beer) :surprise:

 

I was visualizing a single platform going from pole to pole in a non-eliptical orbit. The only time it would be obscured is if a planet (not the sun) was between it and the reciever.

 

Personally, I like the redundancy in multiple smaller systems though.

 

What would cause the high fuel load on the collector?

[Kayra]

ahh now that is a good idea :surprise: eccentric orbit

 

as for the big scoop that collects particles from the vacuum of space - I hear the average particle density is 10^-3 particles per cm cubed, but this sounds wrong - because then even if you had a scoop of cross-sectional area of 100m^2, would only take in 9.6x10^-7 between here and pluto... am I missing something?

 

I would not want to try to collect the acceleration mass from space unless we were moving at near relativistic speeds.

Best to carry some with us, and collect what what we can along the way. (depending on destination of course)

 

In trips to the outer planets at least, a short stop at the asteroid belt to collect some reaction mass might save a lot of time.

[GAHD]

the collector needs to maneuver to send the beam in the right direction.

 

on the geomitry, think about this: take an orange and cut a line in the peel that goes around it simulating a polar orbit, now rotate the orage 90 degrees in any direction except following that line, depending one where the satilite is on that orbit, the sun in the center would obscure it a portion of the time (depending on distance). The sun is not clear, and it's gravity will warp the beam, so redundancy would be necessary. 2 satilites would mitigate this if they orbited non-opposite each other (reflection can't be done 180degrees) but 6 in different orbits (2 x, 2 y, 2 z) gives a much broader range of beam potential and could conceiveably power muliple crafts at a time. useful for electrical power atthe outer reaches at the very least!

[Kayra]

the collector needs to maneuver to send the beam in the right direction.

 

on the geomitry, think about this: take an orange and cut a line in the peel that goes around it simulating a polar orbit, now rotate the orage 90 degrees in any direction except following that line, depending one where the satilite is on that orbit, the sun in the center would obscure it a portion of the time (depending on distance). The sun is not clear, and it's gravity will warp the beam, so redundancy would be necessary. 2 satilites would mitigate this if they orbited non-opposite each other (reflection can't be done 180degrees) but 6 in different orbits (2 x, 2 y, 2 z) gives a much broader range of beam potential and could conceiveably power muliple crafts at a time. useful for electrical power atthe outer reaches at the very least!

 

<furiously drinks more beer>

 

The collector always points towards the sun. the focal point of the collector is a mirror that would simply be steered to reflect the beam in the required direction.

 

I am afraid you lost me completely on the orbit explanation GAHD. Sorry :(

 

As I visualize it (here we go again :note:), imagine your hand is the sun. Take a ball on a short string (our collector) and twirl it around vertically. now, if you face me (the reciever) I will always have a view on the collector.

 

I guess as the ship gradually moves to different points in space, the polar orbit would have to be adjusted so that it always has full face on the reciever. Would that consume a large amount of fuel?

 

I still like the versatility of multiple collectors though.

[Eclogite]

An interesting concept is proposed by Rudolf Meyer.

 

Rudolf X. Meyer The “Flying Carpet” concept: A possible alternative to nuclear space propulsion Acta Astronautica In Press

Abstract

This paper examines the potential performance of a new concept for very high specific impulse propulsion for scientific explorations beyond the solar system. The concept is based on an ultra-light weight solar-electric membrane that is deployed, stretched, stabilized, and oriented by small electric thrusters at its corners. The potential performance is found to be greatly superior to what can be achieved by multiple planetary flybys. The concept is viewed as an alternative to nuclear space propulsion.

 

Flexible solar panels having a weight to power ratio an order of magnitude better than current versions would deliver electricity to a grid which would attract and expel xenon ions. Ions expelled from small nozzles would keep the flexible panels taught and oriented towards the sun. Larger units would drive the sail and 200 kg payload at speeds up to 400,000 mph (still only 0.06% of c), and able to reach Pluto inside one year.

 

If successful I imagine it could be scaled up and man-rated.