Dr. Frank Steier

OHB Bremen

LISA: The first spaceborne Gravitational Wave Observatory

The Laser Interferometer Space Antenna (LISA) is an ESA-led mission in partnership with NASA.
LISA is the first space mission designed to observe the universe via gravitational waves. The mission complements the ground-based observatories and allows to study gravitational wave sources in the mili-Hz regime, providing access to many sources that are not accessible by ground-based detectors.
The LISA observatory consists of 3 spacecraft forming an equilateral triangular constellation of 2.5 million kilometer armlength in trailing Earth-Sun orbit at a distance of about 50 million kilometers to the Earth. Each spacecraft carries two free-floating test masses that are isolated from external disturbances in order to be able to sense the effect of gravitational waves. The resulting length change between two test masses aboard different spacecraft is of the order of 10pm/sqrt(Hz) in the mili-Hz frequency range.
The presentation will give a brief overview on the history of gravitational wave research, the measurement concept of LISA, the design of the three spacecraft and the specific challenges that have to be tackled in the LISA development process.