Situations such as the $165 million Russian Phobus-Grunt space probe failing to reach proper orbit and in danger of falling back to Earth pose unlimited liability risks for the country that carries out the mission, said Professor Frans von der Dunk, a legal scholar on space issues at the University of Nebraska, Lincoln.

If the spacecraft hits Earth and causes danger, Russia “absolutely” is liable and there would be no need for those claiming damages to prove fault, since the causal relationship between the destruction and the Russian probe would be sufficient, von der Dunk said. In addition, there would be no limit, in principle, for damage caused by the probe, he added.

“Consequently, it would certainly be in Russia's interest to warn, as soon as possible, any population likely to be hit in order to allow for evacuation, if possible,” von der Dunk said. An even more interesting and more difficult-to-answer question, he added, would be to what extent the Russians then would be liable for the costs or other damages from any evacuation of people -- whether or not such action is warranted.

More generally, the liability risk applies to all space debris, von der Dunk said. Space lawyers usually define space debris as “man-made,” he added.

In certain instances, it may be difficult to determine the “launching nation” of a given spacecraft and thereby complicate how to address any claims of compensation for damage that may be sustained.

The liability risk also applies to damage caused in outer space to other space objects, not just damage inflicted on the ground. Instances where a “fault-liability regime” applies include the 2007 Chinese anti-satellite missile test and the 2009 Cosmos-Iridium collision in low-Earth orbit (LEO.

“Currently, a lot is happening in the area of trying to address the international problem of increasing generation of debris, though sadly not enough to really turn the tide,” von der Dunk said. On the one hand, acceptance is growing of a customary legal rule that requires boosting a satellite at the end of its lifetime to a graveyard orbit or -- if in low-Earth orbit – letting it burn up in the atmosphere.

But acceptance of those processes is not yet finalized, nor is it widespread enough.

“On the other hand, we're just beginning to understand that we might soon have to spend many millions on cleaning-up operations,” von der Dunk said. “Certain popular orbits, metaphorically speaking, start to look like Mount Everest, if we are to avoid regular satellite failures because of debris hitting, not to mention manned spaceflight being put in danger. The technology is, in some cases, already there -- though untested in real life.”

In other cases, the technology is just “around the corner,” von der Dunk said. The point is that the costs so far seem to outstrip the benefits for any party individually to consider shouldering the financial burden, since the benefits of a mission are for all, while the costs are covered only by the spacecraft’s owner, he explained.

“So, in that respect, there is still a lot to be gained from further international cooperation,” said von der Dunk, who is the author of more than 130 articles and published papers. He also has held the Harvey and Susan Perlman Alumni / Othmer Chair of Space Law at the University of Nebraska-Lincoln’s LL.M. Program on Space and Telecommunication Law since January 2008.

Paul Dykewicz is a seasoned journalist who has covered the development of satellite television, satellite radio, satellite broadband and hosted payloads.