SINE

I quoting again.

Jet Propulsion Laboratory, 3/6/2003: NASA retrieved 11 12 2008:

It is unresolved whether [the Yucatan crater] Chicxulub is the result of a collision with a comet or an asteroid. ‘There are arguments on both sides,’ says the Jet Propulsion Laboratory's Dr. Don Yeomans, who manages NASA's Near-Earth Object Program Office. ‘There are far more asteroids in Earth's orbital vicinity than comets,’ says Yeomans, ‘but most are much smaller than the 10-kilometer size (6.2-mile) of the one that hit Chicxulub. When you get to that size range, then comets are about as prevalent.’

I haven’t met D. Yeomans, but this is what I read.