They are needed for cell phone reception, banking transactions or navigation systems: satellites in space have long been used for more than just research. However, many of the missiles are now inoperable and orbit the earth as space debris. With the help of start-up companies, the European Space Agency (Esa) wants to bring more order. Some companies are hoping for good business.

Together with the Swiss start-up Clearspace, Esa wants to send a robot into orbit that will use its gripper arms to remove debris and defective satellites. Clearspace-1 is due to be launched into space for the first clean-up operation in 2025. "The market is still in its infancy, but we need to promote it," explains Holger Krag, Head of the Space Security Program at Esa. The agency is investing more than 100 million euros in the project. Private investors are also involved in the mission.

There are currently more than 35,000 missiles in space that are larger than ten centimetres. 130 million pieces are smaller than one centimeter. "As with all environmental problems, you have to prevent waste before you clear waste. Are we good at prevention? No," emphasizes Krag. That's why a clean-up campaign is needed. The plan is for the waste to burn up as it enters the earth's atmosphere. In the future, waste should be prevented immediately, says the expert. "We are calling for the object to disappear at the end of every mission from 2030."

Expensive clean-up missions

"Of course, we need several providers. This creates a competitive landscape," explains Krag. The project is still relatively expensive. "Of course, space travel is expensive. A clearance mission is also very expensive, especially the first one," reports the expert. In this area, similar to car production, the focus is on the development of routines. "However, the costs remain in the millions in any case."

Manuel Metz from the German Aerospace Center also sees clean-up missions as a future business model. "The idea is very clear: there should be a prospect of implementing commercial services and applications with it."

Lucrative market for industry?

Octopus-like robots that fish garbage out of orbit are not enough on their own, explains Metz. Rather, there needs to be an interplay between different technologies. "I have the impression that the industry sees a market perspective here. There are various approaches being tested in several countries." Some satellites are already being fitted with specific handles to make it easier to remove the missiles later on. Observation technologies are also important in order to precisely localize the objects.

The Hessian start-up Vyoma, for example, is pursuing such a monitoring strategy. The company wants to use its own satellites to collect real-time data that can localize space debris. In Earth orbit, there are many satellites that have to make evasive maneuvers because the data is sometimes up to 48 hours old, reports co-founder Stefan Frey. Real-time data would improve the prediction of possible collisions with space debris and enable active removal. For example, the data provides information on whether and how fast an object is rotating.

However, collecting data is not cheap. "With ground-based sensors, the price is between 2,500 and 90,000 dollars per month for constant monitoring of an object," reports Frey. The start-up does not want to limit itself to one object, but wants to monitor several. "We have a scaling effect," says the entrepreneur. The monitoring of one object should cost a few hundred euros per month, so that several of them can be monitored.

The first of the two Vyoma satellites is due to be launched in 2024. There are already commercial and institutional customers. "That will be enough to build up a catalog of objects larger than 20 centimetres," says Frey. Ten more monitoring satellites will then follow. After a mission, the satellites will be placed in a specific orbit in order to come down and burn up in the Earth's atmosphere. "We don't want to clutter up space ourselves."

Space debris in the Earth's environment

The latest figures on space debris, provided by the ESA Space Debris Office at ESOC in Darmstadt. The information was last updated on December 22, 2022.