According to a NASA survey, there are approximately 1,000 asteroids in close proximity to Earth that are large enough to cause catastrophic damage if they were to collide with our planet. This survey, known as Spaceguard, was mandated by Congress in 1998 and aimed to locate 90 percent of objects near Earth that are 1 km in diameter or larger. At a conference in San Francisco, astronomer Amy Mainzer of NASA's Jet Propulsion Laboratory announced that the survey is now 93 percent complete. Using the Wide-field Infrared Survey Explorer (WISE) telescope, scientists also discovered around 20,500 smaller asteroids near Earth, a significant finding as previous studies had estimated there were between 36,000 to 100,000 of these objects with a diameter of about 100 meters. Mainzer informed Reuters that while asteroids still have the potential to cause significant damage, the likelihood of a catastrophic impact is low. However, history has shown that a major asteroid strike is possible, as evidenced by the collision of a 5 to 10 km asteroid or comet with Earth 65 million years ago, leading to the extinction of dinosaurs. Mainzer stated that an impact of that size could result in the extinction of most life on Earth. Scientists are currently utilizing archived WISE data to identify potentially dangerous objects that come close to Earth's orbit. As of now, there is no strategy in place for how to proceed in the event that an asteroid is found to be heading towards Earth.