Asteroid positions were computed for every 0.25d in a given year and then compared against the position in the RNGC. If an initial approach within 0.5° was found, the asteroid's position was recalculated using numerical integration at 1-minute intervals for 4 hours on either side of the initial "hit". The final result was the closest position within the 481 tests.

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Calculations by Brian D. Warner.

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