Redwire Space Tests Laser For ESA’s Proba-3 Mission

A recent infrared image captured at Redwire Space in Kruibeke, Belgium, unveils a pivotal laser-based test campaign crucial for ESA’s upcoming precision formation flying mission, Proba-3.

The infrared view of Proba-3's laser-based test campaign taking place at Redwire Space in Kruibeke, Belgium. Credits: ESA/M. Pédoussaut — *The infrared view of Proba-3’s laser-based test campaign taking place at Redwire Space in Kruibeke, Belgium. Credits: ESA/M. Pédoussaut*

Set to launch later this year, Proba-3 aims to deploy two satellites into orbit, creating a meticulously orchestrated “ballet” to maintain formation with a precision down to mere millimeters. This synchronized dance will culminate in the creation of an artificial solar eclipse in space, a feat that promises to unlock unprecedented opportunities for solar observation.

The importance of laser-based positioning system

At the heart of this mission lies a sophisticated suite of sensors, including intersatellite radio links, GNSS, and visual imaging. However, for the utmost precision in positioning, the Proba-3 relies on a laser metrology system, which shoots a laser from one satellite towards a retroreflector on the other, achieving millimeter-level accuracy in tracking relative position and attitude.

Damien Galano, Proba-3’s mission manager, explained more about the calibration process of the laser metrology system: “its performance was tested within the 60-m long Redwire cleanroom,” he said. “The Coronagraph’s laser was reflected off a retroreflector and the resulting positioning measurements checked against absolute ‘ground truth’ using a separate laser tracking system,” Galano explained.

An artist's render of Proba-3's pair of satellites in a highly elliptical orbit around Earth. Credits: ESA/P. Carril — *An artist’s render of Proba-3’s pair of satellites in a highly elliptical orbit around Earth. Credits: ESA/P. Carril*

Notably, behind this ambitious mission stands a consortium led by Spain’s Sener, comprising more than 29 companies from 14 countries. The Proba-3 platforms, crafted by Airbus Defence and Space in Spain, undergo satellite integration by Redwire in Belgium. Additionally, GMV in Spain spearheads Proba-3’s formation flying subsystem, while Belgium’s Centre Spatial de Liège contributes the mission’s main coronagraph instrument.

Mission’s objectives

Scheduled for liftoff aboard the PSLV-XL launcher from India in September, Proba-3 embodies Europe’s pioneering strides in satellite formation flying. By demonstrating precision down to millimeters and arc second accuracy at distances exceeding 144 meters or more for six hours at a time, Proba-3 hopes to open a new era of autonomous space exploration.

Essentially, the duo will function as a unified, autonomous entity, operating independently without ground-based guidance. Following commissioning, standard operations encompass formation flying maneuvers and scientific observations utilizing a large solar coronagraph.

This instrument will obscure the solar disk’s intense light, enabling continuous study of the ethereal solar corona. Notably, due to fuel constraints, each orbit will be partitioned, with six hours dedicated to formation flying at apogee and the remainder to passive safe drifting.

Moreover, the mission’s objectives extend beyond mere technical prowess, aiming to validate strategies for future multi-satellite missions and applications, including Earth observation and in-orbit satellite servicing. Furthermore, Proba-3’s rendezvous experiment holds promise for future endeavors such as Mars Sample return missions and satellite de-orbiting initiatives.