NASA this week announced that it has now discovered more than 10,000 near-Earth objects – asteroids that could pass close to Earth in the future. The agency also bragged that 98% of all near-Earth objects have been uncovered by NASA surveys.

The 10,000th near-Earth object was discovered on June 18, 2013 by the Pan-STARRS-1 telescope on Maui, Hawaii. The telescope is operated by the University of Hawaii, and receives NASA funding. The asteroid, 2013 MZ5, is around 1,000 feet (300 meters) wide but is not considered a potential danger to the Earth.

“The first near-Earth object was discovered in 1898,” said Don Yeomans, manager of the Near-Earth Object Program Office at NASA’s Jet Propulsion Laboratory. “Over the next hundred years, only about 500 had been found. But then, with the advent of NASA’s NEO Observations program in 1998, we’ve been racking them up ever since. And with new, more capable systems coming on line, we are learning even more about where the NEOs are currently in our solar system, and where they will be in the future.”

This new announcement comes just as NASA has issued a “Grand Challenge” to find and combat potentially hazardous asteroids. The agency is accepting ideas on how to locate, explore, and redirect an asteroid, as well as plans to deal with potential “doomsday” asteroids that might be headed toward Earth.

“Finding 10,000 near-Earth objects is a significant milestone,” said Lindley Johnson, program executive for NASA’s Near-Earth Object Observations Program. “But there are at least 10 times that many more to be found before we can be assured we will have found any and all that could impact and do significant harm to the citizens of Earth.”

According to NASA, only around 10% of known near-Earth objects are large enough (over 1 kilometer) to have doomsday-like consequences, were they to hit Earth. Luckily, none of them are on a collision-course with Earth, though the Near-Earth Object Observations program estimates that “a few dozen” of these large asteroids are still undiscovered.

(Image courtesy PS-1/UH)