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180 seconds is a fairly terrible specific impulse... Hydrazine monopropellant has something like 220 seconds, and the new safer monopropellants are comparable (less specific impulse but denser for less tank mass).
Sure but can you refuel with more hydrazine on the Moon? With this new engine, just purify some water and you have more propellant ready to go. Also, is hydrazine so efficient below 30 watts?
Earlier quoted context omitted.
Sure but can you refuel with more hydrazine on the Moon? With this new engine, just purify some water and you have more propellant ready to go. Also, is hydrazine so efficient below 30 watts?
hydrazine works at approximately 0 watts. other than opening a valve it's all chemistry.
180 seconds is a fairly terrible specific impulse... Hydrazine monopropellant has something like 220 seconds, and the new safer monopropellants are comparable (less specific impulse but denser for less tank mass).
Sure but can you refuel with more hydrazine on the Moon? With this new engine, just purify some water and you have more propellant ready to go. Also, is hydrazine so efficient below 30 watts?
But the Isp might be so low only because of scaling issues on a device that has to fit in a microsatellite.
If they do meet their target of 900 second specific impulse on the larger models, then it might indeed be very useful.
Reminds me of some of Isaac Asimov's stories, where all ships are powered by nuclear reactors that flash water into steam for propulsion.
That's an interesting approach. Where did the water come from? Surely they weren't storing it as H20 on the ship? Seems like you'd only want to keep as much as needed for life support in that state. Stored as separate oxygen and hydrogen?
No, no. Water is just the reaction mass. The power source is solar. This is a steam rocket.
Reminds me of some of Isaac Asimov's stories, where all ships are powered by nuclear reactors that flash water into steam for propulsion.
Let's say we found a way to make water the fuel of the future (that is used for all (most) of our needs), should we use it? Isn't water (one of) our most precious resource? Should mankind really risk using (wasting) our precious water? Well, we wouldn't loose it if we use it on earth, but space would be a different story (although, if we only use water as fuel for spacecrafts... it would take a while before we deplet…