A blue-ribbon panel of scientists is trying to determine the best way to detect and ward off any wandering space rocks that might be on a collision course with Earth.

The panel has been commmissioned by the National Academy of Sciences to propose the best way to detect and analyze 90 percent of the “near Earth objects” orbiting between Mars and Venus that are wider than 460 feet by 2020.

About 20 percent of these are identified as potentially hazardous objects because they might pass within 5 million miles of Earth (20 times the distance to the Moon).

More than 5,000 near Earth objects, including 789 potentially hazardous objects, have been identified so far. The scientists predict that future surveys will find at least 66,000 near Earth objects and 18,000 potentially hazardous objects.