Successful test campaign for the GRASS instrument

Successful test campaign for the GRASS instrument


The GRASS (GRAvimeter for Small Solar system bodies) instrument developed within the ESA Hera mission has recently undergone a successful environmental test campaign.

The tests, which were performed in ESA’s Mechanical Systems Laboratory, showed that GRASS is capable to withstand the harsh thermal and air-free environment of space as well as the intense vibrations of the launch.

GRASS is a piece of technology, L-shaped and about the size of two hard drives, developed by the Royal Observatory of Belgium with Spain’s EMXYS company. It will be the first instrument to directly measure gravity on the surface of an asteroid. The gravimeter will be landed on the surface of the Dimorphos asteroid (about the same size as the Colosseum of Rome) aboard the Juventas CubeSat – which will itself be deployed from the Hera mission for planetary defence about the binary asteroid Didymos – and will measure gravity levels of less than a millionth of Earth’s own.

See ESA press release for more information: https://www.esa.int/Space_Safety/Hera/Instrument_to_measure_asteroid_gravity_tested_for_space.

The GRASS gravimeter on a cylindrical shaker.

GRASS gravimeter on shaker. Credits: ESA/EMXYS.