ESA Propulsion Laboratory
What is it for?
The ESA Propulsion Laboratory tests methods of controlling the motion of spacecraft once they have reached space. The violent firing of chemical rockets remains our sole route off the planet, but once up in orbit, the ability to produce precisely controlled, lower-energy thrusts becomes very important to meet mission goals.
In particular the Laboratory has acquired a great deal of expertise on various methods of electric propulsion. This involves applying electromagnetic fields or electric currents to give propellant an extra 'kick' as it leaves a spacecraft engine. Ion thrusters are the best known variant - proven in space aboard multiple missions - in which an electric field accelerates a beam of charged particles, known as ions, away from the spacecraft.
Ion engines and other electric propulsion methods accelerate much more gently than chemical rockets, but they deliver around ten times more thrust per kilo of fuel. And unlike chemical rockets, which can be fired only for brief bursts until their fuel runs out, ion thrusters can run continuously for months or even years – converting sunlight into electricity using solar arrays - building up velocities that no other engine can match.
Electric propulsion holds other advantages for space. Field Emission Electric Propulsion (FEEP) engines, for example, have very low thrust outputs compared to an ion thruster – the standard force exerted is equivalent to that of a falling hair - but deliver a greater degree of precision than any other thruster, opening up many promising applications.
The Laboratory also performs research related to in-orbit chemical propulsion and other advanced techniques.
Last update: 1 September 2009