WEBMAIL    |    Intranet    |    Site Map



Mapping planet Earth with accuracy: ESA’s GENESIS mission

on 25 October 2022

ESA’s Navigation Directorate is planning a new satellite whose results will enable the generation of an updated global model of Earth – the International Terrestrial Reference Frame, employed for everything from land surveying to measuring sea level rise – with an accuracy down to 1 mm, while tracking ground motion of just 0.1 mm per year.

This improvement, at a stroke, will have a major impact in multiple navigation and Earth science applications, including enhancing the precision of the Galileo navigation system. This mission, called GENESIS, is being proposed to ESA’s Council Meeting at Ministerial Level next month.

GENESIS will work by combining and co-locating all four of the main technologies currently used for Earth geodetic measurement on the same platform for the first time, aboard a satellite in a 6 000 km altitude orbit. In the process this satellite will also obtain one of the most precisely determined orbit of any object in space, right down to millimetre scale.

As well as improving our knowledge of the orbits of Galileo – and other Global Navigation Satellite System, GNSS satellites – the data gathered by GENESIS will also allow ‘phase centre calibration’ of GNSS antennas, identifying the offset between their mechanical and electrical centres, which plays a key role in many aspects of positioning, navigation and timing.

In addition, the highly accurate orbital tracking that GENESIS needs to perform its mission, will enable one of the most accurate modelling yet of the non-gravitational forces acting upon satellites in space – such as solar radiation pressure, which is the slight but steady push that objects in orbit receive from sunshine itself.

GENESIS itself will be a relatively small metre-scale satellite, but the challenge will be to synchronise and cross-calibrate its quartet of payloads in a very stable environment, mapping their positions relative to the satellite’s centre of mass down to a millimetre or less during the whole duration of the mission.

More details here.

Image credit: ESA