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A study in 2003 suggested that if asteroid 1950 DA smashed into the Atlantic Ocean, the resulting blast could pack as much energy as a 60,000-megaton explosion, causing tsunami waves at least 200 feet high (60 meters high) to crash against the East Coast.
Unexpectedly, the scientists found 1950 DA is a porous rubble pile, about half of which is empty space. They also discovered that the asteroid is spinning faster than the forces of gravity or friction would allow it to remain in one piece.
Scientists have previously suggested that cohesive forces help keep such rubble-pile asteroids from spinning apart. One possibility is van der Waals forces — weak, short-range electric forces that can attract particles together.
"With such an asteroid, you want to avoid interacting with it directly to prevent it breaking up," Ben Rozitis, an astronomer at the University of Tennessee at Knoxville, told Space.com. "An alternative is to use a 'gravity tractor,' or a heavy spacecraft placed near the asteroid, which uses the force of gravity to pull the asteroid off course."