MICROSCOPE Satellite and its Drag-Free and Attitude Control System

TL;DR

The MICROSCOPE satellite's design and its Drag-Free and Attitude Control System (DFACS) achieved unprecedented low residual accelerations in orbit, enabling highly precise measurements for fundamental physics experiments.

Contribution

This paper details the design, upgrades, and exceptional performance of the MICROSCOPE satellite and its DFACS, setting new standards in drag-free control in low Earth orbit.

Findings

Residual accelerations below 10^{-12} m/s^2 at measurement frequency

Passive thermal control kept temperature variations under 1 μK

Propulsion system provided ultra-low noise, continuous thrust

Abstract

This paper focus on the description of the design and performance of the MICROSCOPE satellite and its Drag-Free and Attitude Control System (DFACS). The satellite is derived from CNES' Myriade platform family, albeit with significant upgrades dictated by the unprecedented MICROSCOPE's mission requirements. The 300kg drag-free microsatellite has completed its 2-year flight with higher-than-expected performances. Its passive thermal concept allowed for variations smaller than 1 $\mu$K at the measurement frequency $f_{\rm{EP}}$. The propulsion system provided a 6 axis continuous and very low noise thrust from zero to some hundreds of micronewtons. Finally, the performance of its DFACS (aimed at compensating the disturbing forces and torques applied to the satellite) is the finest ever achieved in low Earth orbit, with residual accelerations along the three axes are lower than $10^{-12} {\rm m/s}^2$ at $f_{\rm{EP}}$ over 8 days.