Finding SwissCube in space
How do we locate satellites or debris?
Objects in low-Earth orbit measuring more than 10 cm in diameter are tracked from the ground using radar technologies and, in some cases, telescopes.
Based on radar observations, the orbits of specific objects are calculated in order to determine the complete orbit of each object.The observed objects are then linked to existing satellites or to specific collision events and catalogued in a database.
The position of these space objects measuring more than 10 cm in diameter (more than 1 m in Geostationary orbits) are known with limited precision. Therefore, this information will allow us to get within a relative distance of where SwissCube is expected to be and start a lost-inspace procedure to find a more precise location.
Source : ESA/S. Marti,CC BY-SA 3.0 IGO
Finding and moving close to SwissCube in space
CleanSpace One will swipe the search area with various sets of sensors to find the position of Swisscube and initiate the approach. Once SwissCube has been found, CleanSpace One will follow a safe approach strategy in order to get to Swisscube’s location. At a close distance, SwissCube will be formally identified before initiating the capture operation.
This procedure will have to be conducted partly autonomously as the CleanSpace One chaser will only be visible from the operation center when it flies over a receiving station.
Source : EPFL.ch
Capturing SwissCube in space
How do we proceed to capture orbital debris ?
SwissCube is a non-cooperative satellite, meaning that it has been designed with no intention of retrieval once in orbit. It does not have a GPS or any sensor on board to facilitate either an approach or capture, and is likely to be tumbling out of control.
To illustrate this, imagine a cooperative rendez-vous in space being akin to two train wagons drawing closer to one another on invisible rails and seamlessly connecting; whereas a non-cooperative rendez-vous is akin to trying to catch a car that is tumbling across the motorway. The selection of the capture mechanism and the sensors for this operation required years of research and multiple iterations.
Source : SpaceX Starlink satellite constellation
Capturing small versus large debris
The capture of a small satellite such as Swisscube will demonstrate most of the operations required to capture a larger object. Many of the requirements for capture are the same for small as they are for larger objects. A smaller satellite, however, will be more difficult to observe from a distance.
Removing SwissCube from space
What is our solution to remove those debris ?
Once captured, SwissCube will be secured close to the chaser’s body in order to ensure an effective and controlled re-entry of the entire system – the chaser and the target.
In a controlled re-entry, the area of the chaser and the target’s re-entry into Earth’s atmosphere is precisely chosen in order to eliminate any risk to human life or air traffic. The satellites decompose in the upper atmosphere due to heat generated as they re-enter the earth atmosphere at orbital speeds.
As they decompose, several break-up pieces follow their own trajectory, making a relatively long footprint. CleanSpace One is a microsatellite of relatively small size (like a small washing machine), and thus all of its break-up pieces will be burnt before touching the ground.
Source : Kerbal Space Program
In space recycling
Why do we need space recycling right now ?
Today, satellites are not built to be reused or recycled in space. According to the European Space Agency (ESA), it is estimated that there are more 8,100 metric tonnes of known man-made objects in space. The cost of launching a 1 kg object into space can vary between USD 3,000 and USD 50,000.
Despite the fact that the costs of launch are decreasing, it is becomingly increasingly logical and necessary to reuse or recycle structures or satellites in space. Our mission is one of the stepping stones necessary to pave the way for such services as in space re-use and recycling.
Source : ESA/ID&Sense/ONiRiXEL