— Asteroids that might threaten Earth could pose a challenge beyond the obvious, if nations cannot get their act together and figure out a unified plan of action.

There are currently no known space rocks on a collision course with Earth, but with ample evidence of past impacts, researchers say it is only a matter of time before one is found to be heading our way.

A swarm of political and legal issues bedevil any national or international response, including responsibility for collateral damage from deflected asteroids and the possible outcry if one country decides to unilaterally use nuclear weapons to stop an incoming threat.

“The word ‘unorganized’ is spot on here,” said Frans von der Dunk, space law expert at the University of Nebraska-Lincoln. “There is no such thing as even a platform for some level of coordination regarding possible responses – and, to be honest, some quarters very much would like it to remain that way.”

Legal experts discussed such problems April 23-24 at a
conference titled “Near-Earth Objects: Risks, Responses and Opportunities-Legal Aspects.” Their talks underscored how unprepared the international community is to deal with policy and legal fallout from a potential asteroid threat.

Many scientists have already brainstormed a variety of ways to deflect or destroy rogue asteroids, such as sending out spacecraft to nudge the space rock aside for a near-miss or simply blasting it apart. But some solutions may have different levels of appeal for various nations, especially when they involve launching potential weapons into space.

For instance, international concern surrounded a
shootdown of a failed satellite last year, not to mention
‘s 2007 destruction of one of its aging weather satellites with a ballistic missile. Both cases raised worries about the demonstration of satellite-killer technologies.

“The international political reactions to the U.S. shooting down one of its own satellite a year ago to prevent presumably dangerous and toxic fuel from reaching Earth only foreshadows what would happen if the U.S. would detonate nukes claiming to destroy an incoming asteroid,” von der Dunk said.

Other scenarios could highlight the question of international unity. A United Nations Security Council decision on a certain asteroid response likely would shield participating nations against any liabilities for collateral damage from a failed deflection or interception attempt, if the past serves as any guide. For example, the nations participating in the U.S.-led coalition that kicked
out of
in 1991 were not held responsible for damages to
under Security Council mandate.

Von der Dunk also posed the tricky question of what the international response would be if a smaller asteroid was headed for
North Korea
. The politically isolated nation almost certainly would require assistance from the
United States
to deal with an asteroid threat.

Better international cooperation might help in figuring out how to assess asteroid threats and release potentially scary information to the public.

“We have already seen scares raised by scientists ready to put out alarms out there, when either their data … turned out to be considerably flawed, or later data allowed for a much more precise estimate of the risk – which turned out to be much lower,” von der Dunk said.

He pointed to the case of the Apophis asteroid, which astronomers initially gave a 1-in-37 chance of striking Earth in 2029, but later refined the chances of collision to almost zero.

Experts at the conference agreed to keep pushing forward on legal issues, as well as focus on general education on the asteroid threat for policymakers. And they even discussed how private companies might join in the effort to monitor asteroids, potentially for the purpose of extracting mineral wealth from space rocks.