Another ESA rendezvous demo mission proposed
The European Space Agency (ESA) and the Luxembourg startup ClearSpace yesterday announced a new demo mission to test autonomous rendezvous and proximity maneuvers, scheduled to launch in 2027.
PRELUDE aims to validate autonomous rendezvous and proximity operations in real flight conditions. The mission will test high-accuracy tracking, navigation and maneuvering using a combination of vision-based and complementary sensors feeding onboard algorithms and autonomous, fault-tolerant guidance, navigation and control (GNC) software. The goal is to demonstrate full freedom of movement and safe, repeatable maneuvers around another spacecraft.
Sounds good, eh? Not so fast. ClearSpace has had a bunch of these missions proposed, and none has yet flown. In 2019 ClearSpace won an ESA contract to de-orbit an old piece of space junk by 2025. In 2023 however that mission was stymied when that space junk, a payload adapter from a 2013 launch of Vega rocket launch, was hit by another piece of space junk.
Both ESA and ClearSpace apparently had difficulties re-designing the mission. In 2024, the ESA forced a major shake-up in ClearSpace’s management and missions, with the established company OHB taking over the startup. Subsequently the mission was redesigned to de-orbit a different defunct satellite, but delayed until 2029.
In 2024 the United Kingdom gave ClearSpace and Japan’s Astroscale a contract to de-orbit two satellites in ’26. It is however not clear at this time whether that mission will launch as planned.
This new PRECLUDE mission is interesting in that it will test the rendezvous and proximity technology that ClearSpace must have for all the other de-orbit missions. In other words, those other missions were never possible, because ClearSpace didn’t have the capability to do them. This new mission appears designed to develop that capability.
I ask: Why wasn’t PRECLUDE scheduled first, in the first place? That it wasn’t reflects very badly on both ClearSpace and the ESA.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
The European Space Agency (ESA) and the Luxembourg startup ClearSpace yesterday announced a new demo mission to test autonomous rendezvous and proximity maneuvers, scheduled to launch in 2027.
PRELUDE aims to validate autonomous rendezvous and proximity operations in real flight conditions. The mission will test high-accuracy tracking, navigation and maneuvering using a combination of vision-based and complementary sensors feeding onboard algorithms and autonomous, fault-tolerant guidance, navigation and control (GNC) software. The goal is to demonstrate full freedom of movement and safe, repeatable maneuvers around another spacecraft.
Sounds good, eh? Not so fast. ClearSpace has had a bunch of these missions proposed, and none has yet flown. In 2019 ClearSpace won an ESA contract to de-orbit an old piece of space junk by 2025. In 2023 however that mission was stymied when that space junk, a payload adapter from a 2013 launch of Vega rocket launch, was hit by another piece of space junk.
Both ESA and ClearSpace apparently had difficulties re-designing the mission. In 2024, the ESA forced a major shake-up in ClearSpace’s management and missions, with the established company OHB taking over the startup. Subsequently the mission was redesigned to de-orbit a different defunct satellite, but delayed until 2029.
In 2024 the United Kingdom gave ClearSpace and Japan’s Astroscale a contract to de-orbit two satellites in ’26. It is however not clear at this time whether that mission will launch as planned.
This new PRECLUDE mission is interesting in that it will test the rendezvous and proximity technology that ClearSpace must have for all the other de-orbit missions. In other words, those other missions were never possible, because ClearSpace didn’t have the capability to do them. This new mission appears designed to develop that capability.
I ask: Why wasn’t PRECLUDE scheduled first, in the first place? That it wasn’t reflects very badly on both ClearSpace and the ESA.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

