HOUSTON -- NASA is looking for asteroids big enough to destroy an entire city and needs help to find them.
NASA wants Congress to give it $40 million to find the asteroids. They say there are more than 25,000 asteroids in orbit that are at least 328 feet in diameter.
In February a meteor measuring 150 feet crashed into a remote part of Russia, injuring more than 1,000 people and damaging homes and buildings. Even larger meteors could cause multiple fatalities.
NASA is also expected to ask astronomers, scholars and the international community for help.