Czech planetary defence lead Nikola Schmidt: “It is never good to go public about an asteroid threat”

Visualisation: NASA/JPL-Caltech

For nearly two years now, a group of Czech scientists and academics has been working on a national planetary defence strategy for the Czech Republic, funded by a government grant. The leader of the project is political scientist Dr Nikola Schmidt. Asteroids are generally perceived as the greatest threat to Earth from space and so I began by asking him what sizes of asteroids we should be worried about?

Nikola Schmidt,  photo: archive of Nikola Schmidt
“This is among the most common questions we are asked. However, it is important to realise that it is not only about the size of the asteroid, but also about the materials from which it is made of and the angle between the earth and asteroid trajectory.

“A 500m asteroid can demolish the whole of Europe. When it comes to city killers, these can be about 50m in diameter. An important fact is that the higher these objects’ velocity, the more exponential is the damage they can do.”

Can we quantify in percentages what the threat of being hit by a destructive asteroid is?

“We are hit by asteroids every day. When we are talking about so-called city killers, the destructive ones can fall every year. In regard to the overall number of asteroids, we are talking about billions.

“The question is what threshold size do we want to set for the asteroids that we monitor in the solar system? We are currently monitoring asteroids bigger than 240m. That is the task of NASA. When it comes to deciding on whether we will act in response to the threat the United Nations threshold is 50 meters.

“The major group of asteroids in our solar system is called the Asteroid Belt. It lies between Mars and Jupiter. However, when it comes to the hidden asteroids that can suddenly impact Earth, these tend to come from the Sun.

“They are of course also orbiting the sun, but you often don’t have data about their trajectories and simply find them before they hit the earth. That is what happened in Chelyabinsk, Russia a few years ago.

“You don’t see them coming, because they are approaching from the Sun and you don’t see anything coming from the Sun, because detection works on detecting the reflection of sun heat. You do not see them in the visible light spectrum, you see them much better in the infrared spectrum.

“That is why you need to be between the sun and the asteroid. It is also why you have to know the overall situation in the solar system rather than simply being able to quickly detect asteroids approaching the earth.”

Czechia’s role in planetary defence

I imagine there are multiple defence mechanisms that have to be established for protecting the planet against such objects, especially detection and either destruction or course alteration. Does the Czech Republic possess any research centres or radar stations that can help in this activity?

“As my colleagues like to say: ‘An asteroid does not discriminate’.” If you have a country big enough to cover all the requirements necessary for space defence, it is not necessarily mean a correct approach, because you do not want to have one country in the world capable of defending the whole planet.

“The point is that we are supposed to have a global planetary defence capability where several countries can contribute on different agendas and technologies.

“There are voices even within NASA to develop a test mission that would use a nuclear weapon against an asteroid.”

“When it comes to the knowledge capacities we have here in the Czech Republic, it is definitely astronomy. We have great colleagues working at the Institute of Astronomy of the Czech Academy of Sciences in Ondřejov, who are quite special when compared to other institutions in the world, because they have a very specific East European bolide detecting network [European Fireball Network]. This network monitors small asteroids and meteors entering into the atmosphere. It can find out what materials they are made up of.

“Their main contribution lies in figuring out the consistency of asteroids. That is also important in designing a planetary defence mission, because if you would like to strike the asteroid with a kinetic impactor you need to know whether the asteroid is a pile of rubble, or made of iron, or rock. Helping to figure out what asteroids are made of through a network of detectors is not the only capability that the Czech Republic has. Earlier this year, influential scientists gathered in Prague to discuss how the advanced laser technologies being developed in the HiLase laboratory near Prague could be used in constructing a laser that would help explore space. Some Czech laser scientists are working in other centres spread across Europe, which are busy preparing a mission called Hera - a component of a joint European Space Agency and Nasa Asteroid Impact and Deflection Assessment (AIDA) plan.

“What we are trying to do now is develop an instrument that will help us go to the asteroid. The point is that if we can flyby asteroid (which is easier than to sit on its orbit) and fire a laser on it in such a huge velocities, than we can gather huge amount of data because that one space craft can flyby many asteroids during one mission.

“That is very important not just for advances in asteroid mining, but also in having statistical data about asteroids. In other words, where they are coming from and what they are made out of.”

You are currently working on a state funded multidisciplinary analysis of the planet's defence against asteroids, so tell me what role is appropriate for the Czech Republic when it comes to defending the planet?

“I think that a small country such as the Czech Republic can do several things. For example, we should be able to develop not necessarily the whole instrument, but key technologies which make up parts of it and define the national niche when it comes to particular technologies.

“We decided to choose lasers, because of the laser centre we have in Dolní Břežany near Prague.

“There are also other things we can do as a small country. Here, an example would be developing an international foreign policy focused around cosmopolitan ideas, so that other states who possess useful planetary defence capabilities can cooperate with us and the whole wider international community.”

The state of international planetary defence cooperation

Photo: NASA/JPL-Caltech
What is the current state of international cooperation when it comes to external threats to planet earth? I keep hearing about discoveries related to the universe which are joint efforts. However, in terms of defence I also hear for example US President Donald Trump’s plans to establish a Space Force. That aspect seems isolated rather than international.

“Donald Trump fortunately still isn’t thinking about planetary defence. What he is talking about is a Space Force that will defend the satellites or, let’s say, the USA’s national interests in the orbital zone, not beyond.

“If they decide to enforce national interest beyond that zone, we all think and hope this will not be done by weapons, but simply the presence of the United States there. That doesn’t necessarily have to be bad if the US is led by perhaps a more multilateral and cosmopolitan outlook.

“When it comes to the international community there is a body, not necessarily under the United Nations, but triggered by the UN, called Same Page Space Mission Planning Advisory Group. Many countries, including the Czech Republic, are members of it.

“What this group does is it sets up the standards for nations included in Same Page on when members are supposed to raise their hands and say there is a problem. There are, let’s say, warning scales related to things such as when to inform the public, when to start communicating with other countries, when are scientists supposed to confirm and re-confirm trajectories, and so on.

“Furthermore, what we are doing in this group is dividing the work according to national niches, so except for perhaps some exceptionalist nations willing to have their own planetary defence capability.”

You mentioned when you can go public about a threat, so tell me when would you go public? What sort of asteroid would have to be headed towards us to sound an international alarm?

“Personally, I think never. I think there is no way to avoid panic in the world when it comes to a really big asteroid.

“I feel that if you do not go public the governments can work much more effectively, because if you do tell the public politicians will inevitably start their own personal campaigns regarding the publicity of the asteroid threat.

“It is not a widely adopted opinion. There are people within the planetary defence community who believe that we should first tell the people that something is going to happen.

“We would like to establish a consortium of states and scientific institutions which would be able to develop lasers for various applications from orbital removal, to asteroid spectroscopy, asteroid deflection and perhaps even interplanetary and interstellar travel.”

“I do not think that is a good idea. This is a very specific threat, which is supposed to include scenarios regarding how governments are to act in cases of danger and a detected threat. That is what we are supposed to make public - what the scenarios are and how our nations are going to cooperate, not necessarily when it is detected.

“Nevertheless, that is not going to happen. If there is an asteroid like Apophis [450 metres in diameter with earth impact force of 1,200 megatons of kinetic energy] on its way to hit us, we will be watching it on TV every day.”

What would it look like if an asteroid was going to hit the earth right now? We are talking about multi-lateral cooperation, the future, but give me an idea of a case of sudden inevitable impact. Would states cooperate and how would they try to stop this asteroid?

“That is a good question, because if international cooperation guidelines are not written well and settled properly, then it is highly probable that some nation, the United States for example, would simply use the most powerful technology they have and those are nuclear weapons.

“There are voices even within NASA to develop a test mission that would use a nuclear weapon against an asteroid.

“I do not think that is a good idea and in fact we wrote a chapter about it in our book Planetary Defence [academic publication which Dr Schmidt edited]. If you start thinking this way despite the fact that you have other technologies such as a kinetic impactor, gravity tractor, or the lasers I was talking about, you end up in a situation where you are destigmatising nuclear weapons.

“In that perspective they might be used for peaceful reasons and that is a completely different perception of nuclear weapons and not the way we are supposed to go in.

“When it comes to what we are doing and what we think can change very quickly, it is starting the conversation about lasers as a possible instrument for various applications such as deorbiting or moving orbital debris. This is because we have lasers which can track orbital debris and we just need to make them a little more powerful to deorbit objects.

Mr Schmidt says these lasers are not yet in place but are classified, because they are not considered a civilian technology. However, military technology is only one which is considered for use in national defence and of course one states defence is a possible national offensive measure in the eyes of another state.

“Therefore, what we are doing now with lasers is trying to avoid the possibility of their stigmatisation. To make them the foreign policy of a small state.

Visualisation: NASA
“We would like to establish a consortium of states and scientific institutions which would be able to develop lasers for various applications from orbital debris removal, to asteroid spectroscopy, asteroid deflection and perhaps even interplanetary and interstellar travel. After all, the later uses the same photon push lasers, which can be used for various applications.

“The path that we would like to set up is one through science, through civilian applications.

“If you have this technology system in place then no other state can come and say: ‘Hey, we have powerful nuclear weapons. Let’s use them!’. If they only had it themselves, they would not share it with you. They will just say that they are going to save the planet and if someone saves the planet then it will probably be their political system which ends up being imposed onto others.

“Democracies are fragile, so we do not know if we will have a democracy, when nuclear would be used for example by the United States. After all, we can see what is going on there today, democracy is slowly being deconstructed, or reconstructed.”

Moving asteroids with lasers

So, if I understand you correctly, lasers are our big hope right now?

“Lasers are great because they can be used for various purposes.

“They are not necessarily as effective as nuclear weapons. However, if you have developed a laser, you do not have to have it in space. It can be located on the ground.

“When it comes to the security of this laser affecting satellites, there is a very good answer which I was not aware of until recently. If you are pointing this satellite at a target which is several hundred thousand or even millions of kilometres away, then the satellites which are on an orbit closer to earth will simply fly through the laser light but will not be affected.

“This is because you focused the laser towards a distance much farther away from earth. Therefore, these devices can be quite safe for the installations that we have in orbit, while at the same time very useful at deflecting asteroids that are further away.”

“The path that we would like to set up is one through science, through civilian applications.”

So how exactly would such a laser work?

“There are two options when it comes to lasers.

“The first is ablation of the asteroid. That works by heating up the surface of the asteroid which then emits particles. These then have the effect of an engine and the asteroid moves.

“First of all, you have to de-spin the asteroid, which is not complicated at all if you can focus on the desirable spot and then you can heat up the surface, which results in a reaction that moves the object. That is what is happening with comets which we can incidentally measure quite well.

“The other option is a photon push laser, which can also be used for interstellar travel. This does not heat up the asteroid. Rather, it simply hits it with photons which then transfer the momentum of the object, moving it in a different trajectory.

“That is how light sails work and also, for example, how the kinetic impactor against the asteroid works. In that case you have one single spaceship which has a certain weight and that hits the asteroid and deflects it. The point is that you are not firing at an asteroid which will impact Earth within hours, but one whose earthbound trajectory is years in the future.”

The cosmopolitan effect in international relations

You hold a PhD in International Relations and you describe yourself as a cosmopolitan if I am correct?


Is that what led you to becoming interested in this policy area? A belief in international organisations working together.

“Nations are socially constructed. The politicians that we elect on behalf of our nations are trying to speak for them. Do you think one nation can speak on behalf of others when it comes to an asteroid strike?”

“Yes. Definitely. Nations are socially constructed. The politicians that we elect on behalf of our nations are trying to speak for them. Do you think one nation can speak on behalf of others when it comes to an asteroid strike? No, these politicians will have to be pushed towards cooperation.

“We discussed the situation of an asteroid coming towards earth and the United States sending nuclear weapons to stop it. There was actually a nice simulation this year at a planetary defence conference in Washington, D.C., which simulated that an asteroid was going to hit Denver. They nudged it with a kinetic impactor and the area of impact shifted to New York. They wanted to test the aftermath reaction by the Federal Emergency Management Agency.

“The point is that the risk corridor, which is not a single point on the earth, but rather goes around the earth, was crossing Nigeria. That country has a huge uranium deposit. Can you imagine that there will one day be a national planetary defence policy that will aim to nudge an asteroid in a direction that could hit Nigeria and the later state will not want to develop its own nuclear weapons?

“This is a nice example that shows that national planetary defence policy is a nonsense. When it comes to my conviction of being a cosmopolitan in international politics, I believe we need to find examples where cosmopolitan theory is necessary and planetary defence is a case in point.”