Northrop Grumman will supply a scalable space inertial reference unit (scalable SIRU) for Nasa’s global precipitation measurement (GPM) mission.

The scalable SIRU is an inertial reference system that supplies critical rotation rate data that enables the stabilisation, pointing and attitude control of satellites and space vehicles.

The SIRU will be installed on the GPM core observatory satellite.

The GPM mission will study global precipitation from space and the core observatory will serve as the reference standard for precipitation estimates from other GPM constellation spacecraft.

The core observatory is scheduled to launch on 21 July 2013.