NASA's asteroid tracking program can only spot 10 percent of near earth objects (NEOs), making it likely that if the one hits, we won't know until it is too late. The goal of the program is to be able to detect 90 percent of NEOs greater than 140 meters in diameter by 2020, but according to an official audit the current program is way off track.
In 2005, Congress ordered NASA to detect, evaluate and catalog asteroids larger than 140 meters, yet, since 1998, the program has detected 11,000 objects, only 10 percent of the estimated total. (Yes, that does mean that there around 110,000 asteroids near Earth according to NASA.)
A complete list of potentially lethal asteroids can be found here.
There are still positives to take away, and it's important to remember that NASA will most likely detect the largest asteroids, those that can cause global extinctions.
Congress first recognized the need to detect the most dangerous of asteroids, those over 1 kilometer in diameter, in 1992. The government mandated that NASA detect 90 percent of those deadly objects by 2002. NASA succeeded in that goal, but getting the organization and man-power behind detecting slightly smaller objects remains difficult.
NASA Inspector General Paul Martin recently alerted the government in his audit, saying the program is under-funded, poorly managed, and has no clear plan to reach the Congressional mandate.
The report describes the program as organized by "a single program executive who manages a loosely structured, non-integrated conglomerate of research activities with little coordination, insufficient program oversight, and no established milestones to track progress."
The report also describes a number of missed opportunities to work with other government agencies, like the Department of Defense and National Science Foundation, because of a "lack of planning and resources." Working with other organizations would grant the NEO program access to telescopes that would allow them to cover more of the sky.
In all fairness to the NEO program, there is only so much that can be done with a $40 million budget. To put that into perspective, that's about the cost of building two whole high schools. It's also $10 million short of what Bill Gates gave to the World Health Organization for Ebola research (the WHO has raised about $600 million total).
With so many problems in the world, NASA may have lost its sense of urgency. After all, there's already a decent program in place for asteroids over 1km, most other rocks just burn up in the atmosphere.
Nevertheless, some do hit the ground, or get close enough to cause serious damage. In 2013, an asteroid about 18 meters in diameter exploded over the the city of Chelyabinsk in Russia. The mid-air explosion blew out glass windows and injured around 1,500 people with the force of 30 atomic bombs. Had it reached the ground the effect would have been a catastrophe.
Until NASA's program gets back on track, we never know when or where a city-killing space rock comes through the atmosphere. Accidentally spotting one through a telescope might be the way to save thousands of lives.
NASA has accepted the recommendations from the audit and plans to improve its asteroid detection program.
[Image Credit: NASA/Wikimedia Commons]