A U.S. House of Representatives Subcommittee discussed Near-Earth Objects (asteroids and comets in our neighbourhood), in particular those that are classified as Potentially Hazardous Objects (PHOs are larger than about 140 meters across whose orbits bring them close to the Earth's orbit). Objects larger than 50 meters can survive entry through the Earth's atmosphere, and could cause local disasters or events such as tsunamis upon impact. NASA scientists estimate that the population of PHOs is about 20,000 objects, of which we can identify about 900. Estimates of the frequency of impacts of objects of this size range from once every 100 years to once every 500 years. 

Objects larger than 1 km in diameter that impact Earth would cause disasters on a global scale, and "the impact debris would spread throughout the Earth's atmosphere so that plant life would suffer from acid rain, partial blocking of sunlight, and from the firestorms resulting from heated impact debris raining back down upon the Earth's surface." Estimates of the frequency of these range from once every few hundred thousand years to once every million years.

"Extinction-class" objects (10 km or greater in size) are estimated to occur about once every 50-100 million years. The last event of this magnitude occurred on the north side of Mexico's Yucatan Peninsula some 65 million years ago that is thought to have helped bring about the extinction of the dinosaurs and to have destroyed 75 percent of life on Earth.

Partnerships have been formed between NASA, the US Air Force and various institutions with deep space observational capacity. These partnerships are establishing the capacity to identify all potential threats by 2020; launching space missions to better understand comets and asteroids; and establishing the capacity to deflect PHA's using 'impulsive' options such as nuclear ' stand-off explosions' and kinetic impactors, or 'slow push' approaches such as lasers or 'Asteroid Tugs'.

If NASA and the US Air Force are able to divert a PHA and prevent a serious disaster, saving countless lives and alleviating mass suffering, can we consider them 'humanitarian actors'?

Please see the Current projects (military and corporate projects) section of the website for examples of the work that we are doing with new actors.