Asteroid-mining startup AstroForge raises $13 million, books launch for test mission

Catastrophe

"There never was a good war, or a bad peace."
Whilst I appreciate this:
"AstroForge is taking a different tack. The startup doesn't see asteroid water as a particularly promising initial target, given that there's currently no real market for in-space propellant depots."

Re water: "That resource can be split into its constituent hydrogen and oxygen, the chief components of rocket fuel, potentially leading to the establishment of off-Earth "gas stations" for voyaging spacecraft, advocates have said"

Is. not perpetual motion? Apart from travel and transport, is not the amount of energy needed to split water into hydrogen and oxygen the same or greater than the energy you get out of burning them as rocket fuel
'
By the time you do factor in travel and transport costs, surely this is a non starter? The energy you use in getting there plus the energy you split water must be greater than the energy you get out. And how much energy do you really take to get to the water source, and where does it come from? Hydrogen and oxygen? ;)

Cat :)
 
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Dec 9, 2020
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If one is investing hard earned money into this "space mining" project, the R.O.I. has to be better than Earth based mining. Anyone remember the U.S. push to manufacture solar panels even with tax breaks?
 
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Feb 7, 2022
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Whilst I appreciate this:
"AstroForge is taking a different tack. The startup doesn't see asteroid water as a particularly promising initial target, given that there's currently no real market for in-space propellant depots."

Re water: "That resource can be split into its constituent hydrogen and oxygen, the chief components of rocket fuel, potentially leading to the establishment of off-Earth "gas stations" for voyaging spacecraft, advocates have said"

Is. not perpetual motion? Apart from travel and transport, is not the amount of energy needed to split water into hydrogen and oxygen the same or greater than the energy you get out of burning them as rocket fuel
'
By the time you do factor in travel and transport costs, surely this is a non starter? The energy you use in getting there plus the energy you split water must be greater than the energy you get out. And how much energy do you really take to get to the water source, and where does it come from? Hydrogen and oxygen? ;)

Cat :)
The idea of mining water to make fuel is that you can get energy from solar panels to split the water into hydrogen and oxygen. So, you can then recombine them in a chemical rocket engine and use the "steam" as propellant to push the space craft. You could also combine the hydrogen and oxygen in fuel cells to make electricity, and use the electrical energy to accelerate some of the hydrogen in an ion drive. Either way, what you are really doing to "refuel" at an asteroid is to replenish propellant. The energy comes from somewhere else, such as solar panels or maybe a nuclear reactor, even though you get it along with the propellant mass at the asteroid.
 
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Catastrophe

"There never was a good war, or a bad peace."
Yes, but does the ion drive exist yet?

Cat :) :) :)


P.S. Are there not ways of using these other energy sources, such as nuclear, directly? Each cycle is less than 100% efficient so you are losing with each additional stage.
 
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Yes, but does the ion drive exist yet?

Cat :) :) :)
Yes, they do. See https://en.wikipedia.org/wiki/Ion_thruster

Look at the bottom of that link's material for multiple uses on satellites and probes. In particular:
"NASA developed the NSTAR ion engine for use in interplanetary science missions beginning in the late-1990s. It was space-tested in the highly successful space probe Deep Space 1, launched in 1998. This was the first use of electric propulsion as the interplanetary propulsion system on a science mission.[22] Based on the NASA design criteria, Hughes Research Labs, developed the Xenon Ion Propulsion System (XIPS) for performing station keeping on geosynchronous satellites.[92] Hughes (EDD) manufactured the NSTAR thruster used on the spacecraft."

Not exactly "warp drive", but, if I remember the Lagrangian transfer orbits for the outer planets, ion drives beat chemical drives once you get past Mars. Instead of firing for a brief period and coasting the rest of the way, they can provide thrust for most of the trajectory, even decelerating for the latter part of the trip, because they are so fuel efficient.
 

Catastrophe

"There never was a good war, or a bad peace."
I was looking at this:

The ion thruster is not the most promising type of electrically powered spacecraft propulsion, but it is the most successful in practice to date. An ion drive would require two days to accelerate a car to highway speed in vacuum.
Ion thruster - Wikipedia

Cat :)
 
Feb 7, 2022
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I was looking at this:

The ion thruster is not the most promising type of electrically powered spacecraft propulsion, but it is the most successful in practice to date. An ion drive would require two days to accelerate a car to highway speed in vacuum.
Ion thruster - Wikipedia

Cat :)
The acceleration rate depends on the thrust of the ion drive, which depends on the amount of mass expelled and the amount of energy given to that mass. So, it is not dissimilar to a chemical rocket in the sense that there are small ones with little thrust and huge ones with enormous thrust. And, for that car, a 427 cubic inch displacement V-8 will accelerate it much faster than a model airplane 1 cc displacement engine (except of course in a vacuum, where both engines would stall for lack of oxygen), even though they both use the same technology.

Ion drives used for satellite station keeping are intentionally low thrust. But, think about the linear accelerators we use to make atom smashers here on earth. We keep making them accelerate ions faster and faster and able to handle higher and higher densities. They would make much more thrust if just aimed straight into space.
 
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