Spacecraft propulsion (original) (raw)

There are many different ways to accelerate spacecraft. Below is a summary of some of the more popular, proven technologies, followed by increasingly speculative methods.

Propulsion methods

Method Specific Impulse (seconds) Thrust (Newtons) Duration
Conventional propulsion methods
Solid rocket 100-400 103- 107 minutes
Hybrid rocket 150-420 minutes
Monopropellant rocket 100-300 0.1-100 millliseconds - minutes
Momentum wheel (attitude control only) n/a 0.001-100 indefinite
Bipropellant rocket 100-400 0.1-107 minutes
Tripropellant rocket 250-450 minutes
Dual mode propulsion rocket
Air-augmented rocket 500-600 seconds-minutes
Liquid air cycle engine 450 seconds-minutes
Resistojet rocket 200-600 10-2-10 minutes
Arcjet rocket 400-1200 10-2-10 minutes
Hall effect thruster (HET) 800-5000 10-3-10 months
Ion thruster 1500-8000 10-3-10 months
FEEP (Field Emission Electric Propulsion) 10000-13000 10-6-10-3 weeks
Magnetoplasmadynamic thruster (MPD) 2000-10000 100 weeks
Pulsed plasma thruster (PPT)
Pulsed inductive thruster (PIT) 5000 20 months
Variable specific impulse magnetoplasma rocket (VASIMR) 1000-30000 40-1200 days - months
Solar thermal rocket
Nuclear thermal rocket 900 105 minutes
Nuclear electric rocket As electric propulsion method used
Solar sails N/A 9 per km2 (at 1 AU) Indefinite
Mass drivers N/A Indefinite seconds
Tether propulsion N/A 1-1012 minutes
Technologies requiring more engineering development
Magnetic sails N/A Indefinite Indefinite
Mini-magnetospheric plasma propulsion N/A Indefinite Indefinite
Gaseous fission reactor 1000-2000 103-106
Nuclear pulse propulsion (Orion drive) 2000-100,000 109-1012 half hour
Antimatter catalyzed nuclear pulse propulsion 2000-40,000 days-weeks
Nuclear salt-water rocket 10,000 103-107 half hour
Beam-powered propulsion As propulsion method powered by beam
Nuclear photonic rocket 5x106 1-105 years
Biefeld-Brown effect (see also Lifter) N/A 0.01-1 (currently) weeks, probably months
Significantly beyond current engineering
Fusion rocket
Bussard ramjet
Antimatter rocket
Redshift rocket
Requires new principles of physics
Alcubierre drive (Warp drive) Not Applicable
Wormholes
Differential sail
Disjunction drive
Diametric drive
Pitch drive
Bias drive
Time machines

Launch mechanisms

The launch of a spacecraft from the surface of a planet into space places special requirements on the methods of propulsion used. Generally speaking high thrust is of vital importance for launch, and many of the propulsion methods above do not provide sufficent thrust to be used in this capacity. Exhaust toxicity or other side effects can also have detrimental effects on the environment the spacecraft is launching from, ruling out other propulsion methods. Currently, only chemical rockets are used for the launch of spacecraft from Earth's surface.

One advantage that spacecraft have in launch is the availability of infrastructure on the ground to assist them. Proposed ground-assisted launch mechanisms include: