Hi, I'm new here.
I'm asking for a possible propulsion from photovoltaic panels into space.
A question is can electric engines propel into space?
If a wheel run on another wheel and viceversa, then can they propel?
Thanks
QUOTE (Brusca+Oct 17 2009, 06:53 PM)
Hi, I'm new here.
I'm asking for a possible propulsion from photovoltaic panels into space.
A question is can electric engines propel into space?
If a wheel run on another wheel and viceversa, then can they propel?
Thanks
My impression is that electric motors could turn propellors, if they are strong enough, but once the atmosphere gets too thin, they stop working.
I believe there is a technique for propelling a spacecraft in outer space by firing electrons to generate thrust, but it requires a source of electrons, which must be carried along in the craft.
I also believe I heard someone say that solar wind could be somehow harnessed by spacecraft but I'm not sure how that would work. A sail of some sort?
I'm just speculating here. I have to be careful not to sound too authoritative because there are real experts here that know a lot more than I do.
I honestly don't think a photovoltaic solar collector could generate enough power fast enough to achieve orbit. You could use solar power to generate and cool liquid hydrogen fuel to use in a rocket, but you would need a lot of solar cells and it would take a long time, I think.
I'm asking for a possible propulsion from photovoltaic panels into space.
A question is can electric engines propel into space?
If a wheel run on another wheel and viceversa, then can they propel?
Thanks
My impression is that electric motors could turn propellors, if they are strong enough, but once the atmosphere gets too thin, they stop working.
I believe there is a technique for propelling a spacecraft in outer space by firing electrons to generate thrust, but it requires a source of electrons, which must be carried along in the craft.
I also believe I heard someone say that solar wind could be somehow harnessed by spacecraft but I'm not sure how that would work. A sail of some sort?
I'm just speculating here. I have to be careful not to sound too authoritative because there are real experts here that know a lot more than I do.
I honestly don't think a photovoltaic solar collector could generate enough power fast enough to achieve orbit. You could use solar power to generate and cool liquid hydrogen fuel to use in a rocket, but you would need a lot of solar cells and it would take a long time, I think.
Thanks for your answer.
Probably the friction wheel-wheel gives electric engines the possibility to propel into space.
Solar photovoltaic panels have a good power in the space, example:
On the moon
if photovoltaic panels power is about 100 W/m2 on the moon and they need around 780 Wh/kg for winning lunar gravitational energy, then they would go out of lunar gravitation before a terrestrial week.
On the dwarf planet Ceres(It seems to be full of water...)
if photovoltaic panels power is about 14 W/m2 and they need around 37 Wh/kg for winning gravitational energy, then they would go out of gravitation before a terrestrial week.
Probably the friction wheel-wheel gives electric engines the possibility to propel into space.
Solar photovoltaic panels have a good power in the space, example:
On the moon
if photovoltaic panels power is about 100 W/m2 on the moon and they need around 780 Wh/kg for winning lunar gravitational energy, then they would go out of lunar gravitation before a terrestrial week.
On the dwarf planet Ceres(It seems to be full of water...)
if photovoltaic panels power is about 14 W/m2 and they need around 37 Wh/kg for winning gravitational energy, then they would go out of gravitation before a terrestrial week.
I think if you use an electric motor to power a propeller in space you have to have a really huge propeller since the matter in space is so spread out.
You could maybe power a system of electromagnets that attract/repel the magnetism of large bodies of matter like planets to slingshot itself in the direction it needs to go.
You could maybe power a system of electromagnets that attract/repel the magnetism of large bodies of matter like planets to slingshot itself in the direction it needs to go.
Interesting. I didn't know that orbit could be achieved over such a slow ascent. Wouldn't it require a lot more energy to do it slowly, though, since the exposure to gravitational resistance is longer? I guess that only matters when you're carrying your fuel with you, though. If you're using solar energy, you might as well go slow and use more, eh?
Also, I assume you're not talking about a propellor on the moon, but rather some kind of electron-pulse propulsion? I wonder if there is a way to use EM energy only as a propellant. Some kind of laser, maybe? That way you wouldn't have to carry any electrons in the vehicle.
Also, I assume you're not talking about a propellor on the moon, but rather some kind of electron-pulse propulsion? I wonder if there is a way to use EM energy only as a propellant. Some kind of laser, maybe? That way you wouldn't have to carry any electrons in the vehicle.
Regards
QUOTE (light in the tunnel+Oct 24 2009, 01:08 AM)
"I assume you're not talking about a propellor on the moon"
"That way you wouldn't have to carry any electrons in the vehicle."
- serious fuckhead of awesome poppycock.
"That way you wouldn't have to carry any electrons in the vehicle."
- serious fuckhead of awesome poppycock.
Hi light in the tunnel
Lunar gravitational energy is only 780 Wh / kg.
If photovoltaic panels weigh 10 kg/m2 then the energy nedeed to go out of the lunar gravitation is about 7.8 Kwh per m2.
If photovoltaic power is 100 W/m2 then the amount of energy is 16.8 kwh after a week, so they surely have 16.8 - 7.8 = 9 Kwh available for kinetic energy(after a week).
If kinetic energy = 1/2 * 10(weight per m2) * v^2 = 9 kwh then v = around 9000 km/h... (after a week)
Obviously I assume that i don't lose energy, however it's a good speed in order to go out of the lunar gravitation rapidly..
Lunar gravitational energy is only 780 Wh / kg.
If photovoltaic panels weigh 10 kg/m2 then the energy nedeed to go out of the lunar gravitation is about 7.8 Kwh per m2.
If photovoltaic power is 100 W/m2 then the amount of energy is 16.8 kwh after a week, so they surely have 16.8 - 7.8 = 9 Kwh available for kinetic energy(after a week).
If kinetic energy = 1/2 * 10(weight per m2) * v^2 = 9 kwh then v = around 9000 km/h... (after a week)
Obviously I assume that i don't lose energy, however it's a good speed in order to go out of the lunar gravitation rapidly..
WRT an electron propulsion system. Would the following be possible?
Once the electrons are expelled they will be traveling parallel to the direction of travel, just in the opposite direction. Could the electrons be then sent through a positively charged tube which would attract them and catch them? The electrons would be colliding with the tube perpendicular to direction of travel and would be radially uniform for a net difference of 0.
Once the electrons are expelled they will be traveling parallel to the direction of travel, just in the opposite direction. Could the electrons be then sent through a positively charged tube which would attract them and catch them? The electrons would be colliding with the tube perpendicular to direction of travel and would be radially uniform for a net difference of 0.
QUOTE (H2O+Nov 6 2009, 07:31 PM)
WRT an electron propulsion system. Would the following be possible?
Once the electrons are expelled they will be traveling parallel to the direction of travel, just in the opposite direction. Could the electrons be then sent through a positively charged tube which would attract them and catch them? The electrons would be colliding with the tube perpendicular to direction of travel and would be radially uniform for a net difference of 0.
With a net result of zero too. Rockets, including electron rockets, all require the explusion of mass in order to move.
The chief problem with electron rockets is the immense charge they create on the rocket which starts drawing the expelled electrons back towards itself. This is counter-productive.
A common thought is "would the induced charge attract more free electrons so the rocket became self-refuelling?" For a rocket already in motion such electron attraction might allow some electrons to be usefully attracted from the forward direction - BUT there aren't so many free electrons. The ambient plasma of space is neutral - the positive and negative charges balance - and so a net attraction of electrons is also a net repulsion of protons, which creates drag.
Once the electrons are expelled they will be traveling parallel to the direction of travel, just in the opposite direction. Could the electrons be then sent through a positively charged tube which would attract them and catch them? The electrons would be colliding with the tube perpendicular to direction of travel and would be radially uniform for a net difference of 0.
With a net result of zero too. Rockets, including electron rockets, all require the explusion of mass in order to move.
The chief problem with electron rockets is the immense charge they create on the rocket which starts drawing the expelled electrons back towards itself. This is counter-productive.
A common thought is "would the induced charge attract more free electrons so the rocket became self-refuelling?" For a rocket already in motion such electron attraction might allow some electrons to be usefully attracted from the forward direction - BUT there aren't so many free electrons. The ambient plasma of space is neutral - the positive and negative charges balance - and so a net attraction of electrons is also a net repulsion of protons, which creates drag.
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