Since the inception of satellites and human spaceflight, humanity has come to rely heavily on space, but in so doing, it has also produced particles of trash, which number in the hundreds of thousands and whiz around the Earth at over 17,000 miles per hour. For the moment, tracking and avoidance maneuvers have been sufficient to protect Earth’s orbit from becoming severely limited or unusable, but unless cleaned up, these particles of space junk continue to threaten space assets, and could even make space almost unusable if new objects are hit and more clouds of debris added. The Cipher Brief’s Fritz Lodge spoke with Director General of the European Space Agency, Johann-Dietrich Woerner, about the ways in which the world can come together to solve this global problem.
The Cipher Brief: In your mind, how serious is the threat posed to space security and sustainability by space debris?
Johann-Dietrich Woerner: The movie Gravity had many factual mistakes, but the idea that space debris is endangering our space assets is very true. When I say space assets, this is not only the astronauts and the space stations, it is all our space assets. Whether it’s Earth observation, navigation, telecommunication, all of this is now critical infrastructure for our day to day lives, and all of it is endangered by space debris.
TCB: What role does the European Space Agency play in tracking, avoiding, and possibly even removing this debris?
Woerner: The first thing is tracking. Tracking of debris is mainly done in the U.S. but some of it is also done in Europe. We are cooperating with the American side so we are able to receive the U.S. data, combine it with our tracking activities in Europe, and perform collision avoidance maneuvers for our ESA satellites whenever necessary.
This should be about global cooperation – not military or national security – because this is public infrastructure that we are protecting, it is a public good. Tracking of space debris is not a question of nation states, it is a global public good.
The second thing is what to do about this problem. We have about 750,000 particles of at least one centimeter in diameter. This is a huge amount, and the problem is that many of the small particles cannot be tracked at the moment. So we need to take the next step beyond tracking to mitigate the risk, and also to clean the vacuum. To clean the vacuum, we need a vacuum cleaner, and this is not very easy from a technological point of view. So, again, I am pushing for global cooperation to come together on space debris removal.
The easiest things to remove might be the big defunct satellites, which are out of control. We know about some 3,000 derelict satellites, and the still intact ones are relatively easy to remove because you can grab them and bring them to de-orbit. But for the smaller particles, we need a new, better, technology. To do this we need to address this global challenge together irrespective of any national interests.
TCB: What can you tell me about efforts to de-orbit the ESA Envisat satellite?
Woerner: We do not have a mission for de-orbiting Envisat now, but I will propose one at the next ministerial meeting. We are developing technology for this called e.Deorbit, but it is still in development, so we will not start with Envisat the first time we use e.Deorbit, because the Envisat mission is simply too big to fail. If you make a mistake with Envisat and bring it into the wrong orbit, it could be very dangerous for other space assets. Once the technology is proven, we would like to move on to de-orbiting Envisat.
But this is not the only satellite in orbit, there are thousands of satellites that are no longer under control.
TCB: Speaking of this technology, is there a danger that de-orbiting programs like this could be used for military applications? That the same technology used to de-orbit a defunct satellite could be used to de-orbit an adversary’s space asset?
Woerner: I hear this argument every day, and it’s really not a very sound argument.
The argument goes that, if you have a mission which can de-orbit an uncontrolled satellite, you could do the same to another country’s functioning satellite. But you don’t need a robot to do that. To attack a functioning satellite, you only need to build the simplest satellite that you can set on a collision course with the target. Then the deed is done. You don’t need a complicated robot to do that. This is science fiction in the complete wrong direction. If you want to have a war in space, you can do it with the stupidest satellite that you have, there is no need for a complex robot to do so.
Therefore, I don’t see this military argument as a sound argument.
TCB: What is the worst that could happen if we continue to let space debris accumulate?
Woerner: I am not a pessimist. I try to avoid negative future hypotheticals. But we actually had one of our satellites – Copernicus Sentinel-1A – hit by space debris last year, and we saw later on from the onboard camera that part of the solar array was destroyed. Other space crafts have also been similarly impacted by space debris.
There is the so-called Kessler Syndrome, which says that we are already in something like an avalanche, in which the debris is increasing and increasing by hitting other objects and producing more debris – we had this accident between Irridium and Cosmos where thousands of new particles were produced.
But I don’t want to discuss the scenario where something bad happens, I want to discuss the scenario where we can prevent that bad thing from happening. That means that we have to take action right now. I will do it on my personal side by proposing to the European member states of ESA that we begin a space debris clean up mission, but all of us are impacted by space debris and we need a global recognition of this problem.
TCB: Are you worried about the issue of satellite overcrowding? Thinking, for instance, of the Indian launch of over 100 micro satellites in one rocket.
Woerner: These very small satellites are usually not the greatest danger because they often take a rather low orbit. But if you think about the mega-constellations that some companies are starting to pursue, then you have a different situation. These mega-constellations are in much higher orbits, and in these orbits, if you have debris, it will stay for a much longer period. With such constellations, we need to take special measures to make sure we do not produce more debris or cause accidents, and therefore, we need to have a common understanding about how satellites operate. Especially, we need global understanding that after a satellite’s operation is complete, there should be a failsafe de-orbit procedure, which comes into effect if the satellite goes out of operation due to some accident.
TCB: What is the most encouraging thing that you see happening with international cooperation right now, and what else needs to be done to capitalize on that progress?
Woerner: Space debris does not know national borders. It does not know the nationality of any satellite so it endangers everyone equally. Therefore, this is a global challenge to be tackled together.
But it is not as easy as that. Funding is difficult, and only some states have a major stake in projects like the international space station. So we are still pretty far away from true global cooperation on this.
But cooperation is nevertheless critical, and we need this same kind of cooperation when it comes to other objects possibly hitting the earth. Again, a meteoroid doesn’t know that the United States has a border with Mexico, it just lands where it lands. This is a connected activity where I believe we should work together on an international level.
