As scientists attempt to locate and track objects in space that might present a collision risk with Earth, they find themselves facing a vexing question -- if such a potential impact is predicted, how should the public be informed, and warned?
It's a question that was given new urgency in February 2013 when an asteroid created a huge fireball and a window-shattering explosion over the Russian city of Chelyabinsk.
That was ample proof the Earth can't be considered impervious to asteroid strikes, and that some -- like the Chelyabinsk event -- may come with little or no warning.
The United Nations has for years been considering how best to gather information on near-Earth objects (NEOs) to provide advance warnings and notice to national authorities in the case of a possible hazardous NEO approaching our planet.
Their efforts have, in part, led to the creation of an International Asteroid Warning Network (IAWN), which exists independently of the U.N.
At a September workshop hosted by the Secure World Foundation, experts discussed the IAWN and what its policies and processes regarding public information about asteroids should be.
"We made very good progress toward identifying the main issues involved with communicating with the media and public regarding warnings of possible NEO impacts and other related issues," said workshop participant Sergio Camacho, who chairs the U.N. group on NEOs established in 2001.
The IAWN, for its part, held the first meeting of its Steering Committee in January to discuss its role in necessary international efforts to coordinate and develop mitigation measures in the face of any NEO impact threat.
The Steering Committee has not yet reviewed the workshop's results nor has it endorsed or adopted them for implementation, IAWN officials said.
Among the recommendations of the workshop, which convened with a group of experts in near-Earth asteroid science, policy, risk communication and emergency management, was that IAWN should establish a five-year plan intended to make it the globally trusted and credible network for information, notification and warnings regarding NEOs.
That won't be an easy task, the workshop attendees acknowledged, given the widely varying political and cultural contexts of the global audiences that such notifications and warnings would have to reach, with issues of translation and definitions as well as world views and religious beliefs.
"Communicating about any future asteroid threat will not be easy," said Michael Simpson, executive director of the Secure World Foundation. "People will need messages they can act on," he told Space.com, "and they will deserve to know the limitations on what modern science can predict."