The trajectories of low- and high-energy ejecta from the Chicxulub impact crater have been computed using a numerical code and compared with analyses of debris deposited in K/T boundary sections. These calculations indicate that low-energy ejecta produces centimeter- to meter-thick deposits within ~4000 km of the point of impact, although its azimuthal distribution depends on the incident angle of the projectile with the surface of the Earth. The high-energy ejecta or vapor plume rises through the atmosphere and isotropically expands at the top of the atmosphere. The velocity of this ejecta increases as it rises. Approximately 12% of the high-energy ejecta is lost because it reaches escape velocities, while ~25% of the material reaccretes within 2 hours, ~55% reaccretes within 8 hours, and ~85% reaccretes within 72 hours. This ejecta is distributed globally, but it is concentrated around the Chicxulub impact site and at the antipode (corresponding to India and the Indian Ocean 65 million years ago); it is also slightly smeared in a longitudinal direction because of Earth's rotation. Because this debris does not reaccrete all at once, the collisional shock heating of the atmosphere will be drawn out over a period of a few days and will occur in pulses. This could be an important factor when calculating postimpact chemical reactions in the stratosphere. The calculations also indicate the ejecta would have ignited wildfires on several continents around the world, although the distribution of those fires depends partly on the trajectory of the projectile.