Let's build a full scale StarTrek USS Enterprise in space
Discussion
Then we have our resultant 'escape velocity'... from the Suns gravitational pull...
We are circling the Sun at about 67,000mph. using the simple rule of cubed factorial to make a good guess, we'd have to very rapidly accelerate this planet to about 11 times that speed... we would catapult off our present circle at about 750,000mph and we'd have to achieve that acceleration in less than a minute...
That would mean anything not 'tied down' securely would be left behind... water, atmosphere, buildings, us...
Mmmmm, I'm not liking this idea.
We are circling the Sun at about 67,000mph. using the simple rule of cubed factorial to make a good guess, we'd have to very rapidly accelerate this planet to about 11 times that speed... we would catapult off our present circle at about 750,000mph and we'd have to achieve that acceleration in less than a minute...
That would mean anything not 'tied down' securely would be left behind... water, atmosphere, buildings, us...
Mmmmm, I'm not liking this idea.
CBR JGWRR said:
Or we could just slowly move away from the sun, making the orbit much bigger, until eventually we would latch onto the next star's gravity.
It wouldn't have to be instant? (Ok, relatively.)
You can't.It wouldn't have to be instant? (Ok, relatively.)
It wouldn't be like a rocket escaping the Earths atmosphere, the pull of the sun doesn't finish with our orbit, it goes on right out to the outer most planets, something as big as the Earth will be atracted to return to its 'natural' place in the rotational field and it will continue to do so until a little beyond Jupiter and the forces will try very hard to pull us back, you have to 'snap' out of orbit or you can waste all the energy in the Universe as you won't loosen the Suns grip.
I'll try to say that less clumsily...
You have to apply the energy as tangentially to our present orbit as would be possible, if you didn't all that energy would just speed our course around the Sun... and that would also cause a huge gravitational collapse, probably catastrophic for our entire solar system...
As would our leaving it actually! The 'hole' created would cause all the planets left behind us to shuffle and collide as the gas giants would take a huge knock and Jupiter might well ignite into a rather weak red sun, first falling in then exploding into a binary with our Sun, with such proximity that would be f
king spectacular! Really really fking spectacular...
You have to apply the energy as tangentially to our present orbit as would be possible, if you didn't all that energy would just speed our course around the Sun... and that would also cause a huge gravitational collapse, probably catastrophic for our entire solar system...
As would our leaving it actually! The 'hole' created would cause all the planets left behind us to shuffle and collide as the gas giants would take a huge knock and Jupiter might well ignite into a rather weak red sun, first falling in then exploding into a binary with our Sun, with such proximity that would be f
king spectacular! Really really fking spectacular...
Plus... if we did just accelerate on present path rather than tangentially then we will go straight into the sun!
The faster your rotation around the sun, the closer you have to get as the energy has to equal the square of velocity principal and if we miss timed the energy burst that would have to be in exactly the opposite direction to the sun, the square law would drag us back and into the sun.
The faster your rotation around the sun, the closer you have to get as the energy has to equal the square of velocity principal and if we miss timed the energy burst that would have to be in exactly the opposite direction to the sun, the square law would drag us back and into the sun.
CBR JGWRR said:
So we are better off building spacecraft then.
It certainly strikes me as being less suicidal.An elevator is a good idea, but difficult.
We need 4 things to make space travel (proper space travel) possible.
1/. A propulsion system that converts energy directly into thrust, nuclear, not chemical. At present the designs we have only an efficiency ratio (taking conventional as 1.0) of 2.5, we'd need a ratio of 1,000,000 to 1
2/. A way of damping inertia. At present we can't even accurately tell ourselves exactly what causes inertia at its base, so that is quite some time off...
3/. We then have to make it big enough to hold all the above apparatus and have a few people and their life support on board.
4/. A guidance system and reference system to navigate and control this monster. Pulsars are not actually moving in the cosmos much and the movement they have is stable because everything but Black Holes get out of their way and are not slowed in the slightest if they hit and destroy solar systems such as ours, they don't even have their course deflected by such encounters. So we have a good basis for a 'GPS' in the outer reaches of space and Pulsars have unique signatures so it has great GPS potential... it's the computers that couldn't cope and the craft itself...
Edited by Gene Vincent on Tuesday 15th May 20:32
you guys are thinking like 20th century humans, do you really think the great ocean-going expeditionary voyages of the 15th and 16th centuries, and the people emigrating to the new world around the same time were concerned about getting home? They took cutting edge technology beyond the edge of the known world, they didn't know what they find, or if it would cope. any interstellar expedition will involve similar risks and leaps of faith - you can't do it in a modern 'risk assesment' style. the same for manned missions to mars, etc.
Gene Vincent said:
As would our leaving it actually! The 'hole' created would cause all the planets left behind us to shuffle and collide as the gas giants would take a huge knock and Jupiter might well ignite into a rather weak red sun, first falling in then exploding into a binary with our Sun, with such proximity that would be fking spectacular!
The interplanetary version of Greece leaving the Euro...king spectacular!Use Psychology said:
you guys are thinking like 20th century humans, do you really think the great ocean-going expeditionary voyages of the 15th and 16th centuries, and the people emigrating to the new world around the same time were concerned about getting home? They took cutting edge technology beyond the edge of the known world, they didn't know what they find, or if it would cope. any interstellar expedition will involve similar risks and leaps of faith - you can't do it in a modern 'risk assesment' style. the same for manned missions to mars, etc.
Very good point. Though they did at least know there would be air to breathe at the other end, and probably water and food. But it does make you wonder how many explorers left and never made it back, and we have no idea.
From the 1st link here - http://www.gizmag.com/engineer-proposes-uss-enterp...
"Though similar in scale and appearance to the USS Enterprise ("it ends up that this ship configuration is quite functional," Dan writes), the "Gen1 Enterprise" would be functionally very different. Firstly, the main nuclear-powered ion engine (boasting 1.5 GW of power) would strictly limit the Enterprise to intra-solar system missions, being incapable of anything approaching faster-than-light speeds. However, Dan claims that the Gen1 would be capable of reaching Mars from Earth within ninety days, and reaching the Moon in three. Comparatively rudimentary compared to the NCC-1701 portrayed on screen, Dan's Gen1 proposal is somewhat analogous to the real world "Tricorder" we looked at last month, being one imaginary technology scaled back to meet present day technological possibilities - though obviously this is a rather more ambitious scheme.
Dan claims that the Gen1 would have ample living space and could generate gravity of 1 g. This would be created by a rotating magnetically-suspended gravity wheel housed within the Enterprise's familiar saucer-shaped section. A counter-rotating ring is also proposed in order to prevent the body of the ship rotating. Dan suggests that the second ring might be filled with water, propellant, or other materials that would be needed aboard ship"
"Though similar in scale and appearance to the USS Enterprise ("it ends up that this ship configuration is quite functional," Dan writes), the "Gen1 Enterprise" would be functionally very different. Firstly, the main nuclear-powered ion engine (boasting 1.5 GW of power) would strictly limit the Enterprise to intra-solar system missions, being incapable of anything approaching faster-than-light speeds. However, Dan claims that the Gen1 would be capable of reaching Mars from Earth within ninety days, and reaching the Moon in three. Comparatively rudimentary compared to the NCC-1701 portrayed on screen, Dan's Gen1 proposal is somewhat analogous to the real world "Tricorder" we looked at last month, being one imaginary technology scaled back to meet present day technological possibilities - though obviously this is a rather more ambitious scheme.
Dan claims that the Gen1 would have ample living space and could generate gravity of 1 g. This would be created by a rotating magnetically-suspended gravity wheel housed within the Enterprise's familiar saucer-shaped section. A counter-rotating ring is also proposed in order to prevent the body of the ship rotating. Dan suggests that the second ring might be filled with water, propellant, or other materials that would be needed aboard ship"
Bedazzled said:
(Putting practicalities aside) that's not how it works at all. The most efficient means to escape the solar system is to wait until Earth is at perihelion (nearest point to sun) and then thrust forwards (along the trajectory of Earth's orbit) to increase speed until the apoapsis (furthest point on the far side of the Sun) leaves the solar system and intersects the target star. When you approach apoapsis you will be captured by the gravity of that object. It's a bit more complicated because of the gravitational influence of the other planets, but it's basically how Apollo went to the moon.
The stuff about the Earth being attracted to snap back into its natural place and going straight into the sun is rubbish, the Earth's orbit depends entirely on its mechanical energy (KE+PE). If you speed up the Earth it will increase the mechanical energy, so the far side of its orbit will move further away from the Sun (translating KE into PE). Thrusting perpendicular to its trajectory doesn't change the mechanical energy of the orbit at all, it just changes the shape to become more elliptical.
Any speeding up of the Earths present course will mean we career into a closer orbit and the sort of increase we are talking about (11x present) means we are travelling 6x faster than Mercury in its orbit.The stuff about the Earth being attracted to snap back into its natural place and going straight into the sun is rubbish, the Earth's orbit depends entirely on its mechanical energy (KE+PE). If you speed up the Earth it will increase the mechanical energy, so the far side of its orbit will move further away from the Sun (translating KE into PE). Thrusting perpendicular to its trajectory doesn't change the mechanical energy of the orbit at all, it just changes the shape to become more elliptical.
This is the 'prime mover' in this matter and as such over powers any/other effects.
Your ideas work only for objects that are small in scale or rather comparison, a Saturn 5 is big to us but minute in this comparison.
The orbits of the planets determine their speed in that orbit and is a balancing act, accelerate and you get closer... now if you slowed us we would move out gradually, halve our orbit speed and we are in the same orbit as Jupiter, halve it again and we're beyond Neptune.
We're too massive to get a 'slingshot' as the Apollo mission did.
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