1. Why did Asteroid 2019 OK cause concern among scientists? * The asteroid was not detected until it was extremely close to Earth. It's the largest known near-Earth asteroid ever discovered. The asteroid's path was aimed directly at the moon. The asteroid was too large to be deflected away from Earth

The asteroid was not detected until it was extremely close to Earth.

Explanation:

According to data from NASA, the Asteroid named 'Astriod 2019 OK', was detected when it was extremely close to earth with just about an estimated distance of  73,000 kilometers  (45,000 miles) from the Earth.

Scientists were concerned at the proximity of this space object to the Earth before it was discovered, and it brought about a cause of concern that since it was not extremely large (estimated 57 to 130 meters wide) it creates a potential for other smaller asteroids to escape detection and struck the earth.

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