What benefits does the ESA Propulsion Laboratory deliver?
Working closely with ESTEC mission project teams, the Laboratory's research during the last two decades has underpinned ESA's adoption of ion thrusters for space. Having been exhaustively qualified on the ground, the technology was then proven for space with test spacecraft SMART-1 and Artemis. Now deep-space missions BepiColombo and Solar Orbiter will be employing ion engines to fly closer to the Sun with less fuel mass than purely chemical propulsion would permit.
As well as contributing to mission design, the Laboratory also extends its support to missions in flight. One example is the Artemis communication satellite, launched into an incorrect orbit in 2001. Mission managers sought to use its experimental ion thruster to gradually move the satellite 5000 km in altitude. The Laboratory then performed an endurance test of the thruster to verify it was capable of such sustained firing. Testing confirmed the manoeuvre was feasible, and Artemis finally reached its planned orbit 18 months of thruster firings.
The Laboratory has also made considerable progress in both electric and chemical micropropulsion, delivering unprecedented precision spacecraft control with numerous scientific applications.
Among the most notable is ESA's Darwin mission, which involves multiple free-flying telescopes positioned so precisely that they can combine incoming light to resolve high-resolution images of Earth-like exoplanets, the Gaia mission to map stellar positions in three dimensions as well as LISA, where laser-linked spacecraft will attempt to detect gravitational waves predicted by Albert Einstein.
Almost incidentally to its main task, the Laboratory has also extended scientific and technical knowledge of plasmas, the clouds of charged particles produced by ion thruster firings. This is valuable because naturally-occurring plasmas can interfere with spacecraft systems, in the worst case inducing damaging 'space lighting' known as electro-static discharge.
These plasmas have additional potential in the field of aerothermodynamics, the study of how gases flow around space vehicles at high velocities. In particular, the friction of atmospheric re-entry surrounds a spacecraft with a ball of hot plasma. Plasma plumes are therefore being considered for use on an experimental basis to supplement traditional wind tunnel re-entry testing.
Finally, the Laboratory also coordinates a European network of industrial and academic propulsion laboratories known as EPNET, serving to pool test resources when required and establish common test standards.
Last update: 29 September 2009