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Magnetoplasma drive could make Mars transit take 39 days?

orbitalindex.com

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Re: Magnetoplasma drive could make Mars transit take 39 days?

#2
"A massively scaled up version running at 200 MW could make the one-way transit to Mars in as little as 39 days, but generation of this amount of in-space energy isn’t currently anywhere near possible and would require both an advanced onboard nuclear reactor as well as super-efficient heat radiators. "

200 MW is a helluvalotta power! Disappointing to see it's so far off.

Re: Magnetoplasma drive could make Mars transit take 39 days?

#3

"A massively scaled up version running at 200 MW could make the one-way transit to Mars in as little as 39 days, but generation of this amount of in-space energy isn’t currently anywhere near possible and would require both an advanced onboard nuclear reactor as well as super-efficient heat radiators. " 200 MW is a helluvalotta power! Disappointing to see it's so far off.

But usage on smaller, uncrewed probes could be much closer.

Re: Magnetoplasma drive could make Mars transit take 39 days?

#4

"A massively scaled up version running at 200 MW could make the one-way transit to Mars in as little as 39 days, but generation of this amount of in-space energy isn’t currently anywhere near possible and would require both an advanced onboard nuclear reactor as well as super-efficient heat radiators. " 200 MW is a helluvalotta power! Disappointing to see it's so far off.

How much thin film PV is that? There's no wind and the solar constant is a lot higher in space even further from the sun.

Also remember that space is not dark. Unless you are behind something you are always in daylight if you are near a star.

Re: Magnetoplasma drive could make Mars transit take 39 days?

#5

"A massively scaled up version running at 200 MW could make the one-way transit to Mars in as little as 39 days, but generation of this amount of in-space energy isn’t currently anywhere near possible and would require both an advanced onboard nuclear reactor as well as super-efficient heat radiators. " 200 MW is a helluvalotta power! Disappointing to see it's so far off.

If we're talking of this kind of efforts, why not to discuss this - https://toughsf.blogspot.com/2019/10/the-expanses-epstein-dr... . Seems in the realm of physics, with some more impressing results...

Re: Magnetoplasma drive could make Mars transit take 39 days?

#6
post #5

"A massively scaled up version running at 200 MW could make the one-way transit to Mars in as little as 39 days, but generation of this amount of in-space energy isn’t currently anywhere near possible and would require both an advanced onboard nuclear reactor as well as super-efficient heat radiators. " 200 MW is a helluvalotta power! Disappointing to see it's so far off.

If we're talking of this kind of efforts, why not to discuss this - https://toughsf.blogspot.com/2019/10/the-expanses-epstein-dr... . Seems in the realm of physics, with some more impressing results...

Yeah this sounds cool. Essentially you could design a large spacecraft and put a fusion reactor in it (we will have viable, positive yield reactors soonish). It should be possible then to power a fusion drive as well by building a sort of "half-open" fusion reactor chamber into which we dispense some of the plasma without any pressurization. It should essentially cause a massive explosion, that if somehow controlled by magnetic fields, should yield an enormous forward thrust.

Technically, does it even matter how fast we eject? Shouldn't relativity allow us to reach speed of light with any positive thrust velocity? If the speed of the shuttle was of any concern, that should directly invalidate relativity, since passengers would suddenly not perceive any acceleration anymore, even though nothing about the spaceship and its physical reaction has changed.

Re: Magnetoplasma drive could make Mars transit take 39 days?

#7
post #4

"A massively scaled up version running at 200 MW could make the one-way transit to Mars in as little as 39 days, but generation of this amount of in-space energy isn’t currently anywhere near possible and would require both an advanced onboard nuclear reactor as well as super-efficient heat radiators. " 200 MW is a helluvalotta power! Disappointing to see it's so far off.

How much thin film PV is that? There's no wind and the solar constant is a lot higher in space even further from the sun. Also remember that space is not dark. Unless you are behind something you are always in daylight if you are near a star.

The linked article also makes a comparison with the ISS solar arrays, which provide 120kW of power. They're not the most efficient panels out there, but it's hard to make up three orders of magnitude.

Re: Magnetoplasma drive could make Mars transit take 39 days?

#8
From what I heard from industry people, overheating is an unsolved problem for VASIMR. It is 60-70% efficient, meaning that 60kW of thermal power has to go somewhere.

Waste heat management for 200MW system in space is firmly outside the realm of present-day technology.

Re: Magnetoplasma drive could make Mars transit take 39 days?

#9
post #4

"A massively scaled up version running at 200 MW could make the one-way transit to Mars in as little as 39 days, but generation of this amount of in-space energy isn’t currently anywhere near possible and would require both an advanced onboard nuclear reactor as well as super-efficient heat radiators. " 200 MW is a helluvalotta power! Disappointing to see it's so far off.

How much thin film PV is that? There's no wind and the solar constant is a lot higher in space even further from the sun. Also remember that space is not dark. Unless you are behind something you are always in daylight if you are near a star.

On Earth a commercial solar panel produces around 150W per square meter peak. I don't think you can improve this by more than an order of magnitude. Solar power drops off with the square of the distance to the sun. 200MW is a lot of solar panels.

Re: Magnetoplasma drive could make Mars transit take 39 days?

#10
Using nuclear bombs for propulsion was estimated to make it to Mars and back in 4 weeks. First time I heard of this, I thought it was a joke.

https://en.wikipedia.org/wiki/Nuclear_pulse_propulsion

The project Orion study anticipated a one-way trip could reach Alpha Centauri in as short as 133 years

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