PAUL CHODAS
JPL/Caltech
MS 301-150
Jet Propulsion Laboratory
4800 Oak Grove Dr
Pasadena CA 91109
Paul.Chodas@jpl.nasa.gov
Abstract:
The probability that a known asteroid or comet will collide
with the Earth during a future close passage depends on its orbit
uncertainties during that encounter. The equations of motion for these
objects are very accurate: orbit uncertainties are primarily due to the
uncertainties in the observations from which orbits are computed. To
estimate collision probability, we use a Monte Carlo technique to map
orbital uncertainties at the time of the observations to target-plane
uncertainties at the time of the encounter. One asteroid last year had
an estimated impact probability on the order of 1 in 500,000.
Fortunately, additional observations reduced its orbit uncertainty and
drove this probability down to near zero.