Principle of STE-QUEST measurements - gravitational redshift
![](https://cdn.sci.esa.int/documents/33940/35451/1567216846854-RedShift_screen.jpg)
Date: 07 September 2011
Satellite: STE-QUEST
Copyright: ESA
A two-way link compares the clock on-board the STE-QUEST spacecraft (νsc) with two clocks on the ground (ν1 and ν2). The link transfers the clock signals in both directions (space-to-ground and ground-to-space) allowing the received signal to be compared with the local clock at both ends.
Last Update: 1 September 2019