🚀 go-pugleaf

Any idea what kind of engines the "Discovery" and "Alexei Leonov" of "2010 -
Odyssey Two" were using? Obviously, they have to be pretty fuel-efficient [=an
exhaust velocity of at least 25km/s] since neither craft seems to have much
room for fuel aboard. Ion engines seem to be out of the question but what about
a fusion-powered plasma motor? The visual appearance of the nozzles [=not
bell-shaped like those of the Space Shuttle or a nuclear engine] plus the 
fact that both vessels have clusters of small engines rather than three or 
four big ones all suggest that the exhaust jets produced by the engines 
contain little mass, but are being ejected at high velocities.
---
Does anyone know what the theoretical maximum exhaust velocity for an
"economical" fusion/plasma engine is, using standard propellants like methane,
water or hydrogen?   
> 
> MARCU$
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> Marcus Lindroos                             Internet:     mlindroos@abo.fi
> Computer Science
> Abo Akademi University
> Finland