NASA is claiming a major victory as its latest calculations suggest it has reached a congressionally-mandated target of finding more than 90% of near-Earth asteroids capable of causing a planet-wide catastrophe.
Calculations using observations made by the recently-retired WISE (Wide-field Infrared Survey Explorer) telescope, shows that 911 of an estimated 981 near-Earth objects over one kilometre in size have been discovered. None are thought likely to hit Earth
“We thought this warranted a press conference. It’s something we’ve been working towards for 12 years now,” Lindley Johnson NASA’s Near-Earth Object program executive, tells Nature.
In 1998, Congress mandated that NASA find 90 per cent of asteroids in this category. But in 2005, that goal was extended to include 90% of asteroids down to 140 meters in size — and NASA is nowhere near there yet. Prospects for reaching that goal appear howver to have dramatically improved today, as calculations by the Near-Earth Object WISE team released today show that the likely population of medium-sized objects between 100 metres and one kilometer in size is smaller than thought – around 20,000 as opposed to the 35,000 that had been estimated.
Asteroid exploration has been a priority of US president Barack Obama and has boosted efforts on planetary defense and near-Earth asteroid discovery. In October 2010, the White House Office of Science and Technology Policy assigned NASA as the lead agency on planetary defense, Nature reported.
Image: From NASA/JPL.