Monday, January 22, 2007

Space Debris and the Chinese Anti-Satellite Test

You’re walking with your family down a street early on a Sunday morning. It’s not very crowded. There are a few other early risers about. Then, this guy steps out from an alley, throws a ball into the air, takes his shot gun, and shoots at it.

He’s using the tennis ball for target practice, and is not taking any care as to what might be on the other side of the ball. He is a lot like Dick Cheney hunting birds – not overly concerned with what might be standing in the direction of where he might be shooting. Only, the two cases would be similar if Dick Cheney had said in advance to his hunting companions, “You had better watch out. If I get a shot I’m taking it, and if you’re in the line of fire, so much the worse for you.”

The incident that I am referring to is a Chinese test to destroy a satellite in orbit.

Moral Responsibility for Creating Risk

I condemned Cheney for the moral irresponsibility of his hunting accident. A hunter has an obligation to know where his shells will land after he fires his gun. If he does not know, he is in the wrong.

This destruction of a space satellite is orders of magnitude worse than Cheney’s hunting accident.

Cheney’s shotgun fired a small hand full of pellets at a velocity of about 1300 feet per second. If they had not hit his friend (or the bird) they would have been rendered harmless in just a few seconds.


China’s test created two debris clouds (one associated with the attack craft, and one associated with the satellite that was hit) with mass equal to that of both satellites, traveling at a velocity of about 25,000 feet per second. As reported in the Center for Defense Information fact sheet on space debris

Even tiny pieces of debris can damage or destroy satellites, the Space Shuttle, the ISS, or penetrate astronaut suits. Debris in LEO travel at 10 times the speed of a rifle bullet; a marble-sized bit of junk would slam into a satellite with the energy equal to a 1-ton safe hitting the ground if dropped from a five-story building. Indeed, a tiny paint fleck put a pit in the window of the Challenger Space Shuttle during Sally Ride’s historic first mission.

This same report also states:

NASA data shows a current risk of a “catastrophic” debris strike to the Shuttle of 1 in 200. By comparison, the lifetime risk of a U.S. citizen dying in a car accident is about 1 in 100; the risk of dying in an attack with a firearm, about 1 in 325; the risk of dying in a fire, about 1 in 1,116.

These figures are just for the Shuttle. Add the Intentional Space Station, and any private plans to put people into space for research, tourism, or the use of space resources to try to take some of the strain and risk off of Earth’s ecosystems, and it becomes apparent that these people are creating a serious hazard.

Of course, China is not the only culprit in this crime. The former Soviet Union put satellites and spent boosters into orbit that tended to blow up as they decayed. The United States has conducted its own anti-satellite weapons test that left their own debris fields circling the earth.

It seems that moral irresponsibility in these matters is an international standard.

Knowingly Causing Harm

Scholars recognize four levels of culpability when it comes to moral wrongdoing. A person intentionally kills another if he grabs a gun and aims it and kills another. He knowingly kills another if he shoots a gun in order to kill a bird, knowing that it will kill the person on whose nose the bird id perched. He is reckless if he knows that his actions increase the chance that others will die, and negligently kills others if a reasonable person would have known that such an action could cause death.

Cheney’s hunting accident was a case of recklessness wrongdoing. I am assuming that he was aware of the fact that somebody who pulls the trigger of a gun when it is pointing at somebody else would do harm. His act was not negligent because he would not have likely been surprised to discover that his sport was dangerous.

China’s moral crime is one of knowingly doing wrong – of creating a risk to others under circumstances where there is no doubt but that they knew of the risk, and did not care.

One of these days, we are going to have an astronaut on a space walk suddenly experience the effects of a marble-sized one-ton safe hitting him. When that happens, there will be somebody far more careless and irresponsible than Cheney responsible for that death.

Externalities and Compensation

Ultimately, this type of activity counts as a new form of pollution. People who engage in these types of activities are creating “negative externalities” for others.

It’s a bit like walking into a restaurant, ordering a fine meal, and paying for it on a stolen credit card. China (following an example set by other space faring countries) bought its satellite demonstration using a credit card that will some day send a bill – in the form of a screw or shard of metal – flying through somebody’s body at over 17,000 miles per hour.

Whenever somebody is allowed to take some good for free, they inevitably take far more of it than they need. They end up making the world a worse place than it would otherwise be, because what they take from others is worth far more to them than the it is to the person who takes it. If the thief has to actually pay for what he takes, he would soon discover that he values the object less than what he would have to pay to purchase it honestly.

Similarly, if people were forced somehow to pay for the orbital pollution they create – pay enough to compensate others who they put at risk of harm – they would likely discover that the risks they create really are not worth the benefits they receive. They will almost certainly discover ways to reduce the risk, in order to reduce their bill. This, in turn, will put a barrier against the incentives that are causing them to make the world worse than it would otherwise be.

Accepting Responsibility

From here, it seems natural to go on to talk about a need for a treaty or some sort of international contract that says that countries will pay some fee or fine when they create a debris field. The money would somehow go into some fund that would then be used to offset the costs of these debris fields – the extra money that must be spent on hardening spacecraft against collision and the eventual, inevitable death of an astronaut.

However, a person (or a country) does not need to have a law to act in a morally responsible manner. A morally responsible slave owner did not need to wait for the Emancipation Proclamation to free his slaves – he could have done the right thing the instant he recognized what it was. The person who hits a parked car at night, where there are no witnesses, may be able to drive off and never get caught. Or he could accept responsibility for his actions and take steps to compensate those who he has harmed.

A nation can do the same thing.

A nation that tries to get away with doing harm to others just because it can has the moral character of a hit man, killing for profit. It is a simple matter for a government to admit, “Our actions create costs for others. We accept responsibility for the potential harm our acts may cause, and take the following actions as acknowledgement of that responsibility.” An appropriate response would be to quite voluntarily establish a fund to compensate any future person or organization that suffers physical damage or costs as a result of this space debris.


There may be more at stake here than just the loss of a few astronauts or catastrophic damage to some orbiting habitats and satellites. As I have written in the past, we live in a universe that is indifferent to our survival. Whether (and for how long) we survive as a species depends on the choices we make.

One option that would significantly increase our odds of survival as a species is to of those choices is to put an end to this state where we keep all of our eggs in one planetary basket. As a solar-system wide species, we can survive any calamity that may befall Earth.

Instead, we are creating a situation where we may be confined to the Earth because we surrounded ourselves with a debris field that is too risky to live in. These are human actions – human foolishness at work.

1 comment:

Anonymous said...

just good to know

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