Periapsis vs. closest approach
Jacob Samorodin wrote:
The DS-1 spacecraft is supposed to attain a periapsis [closest approach]
of some 2000km [1250 miles] from Borrelly's nucleus.
Alex writes:
Just a nit: Periapsis refers to the distance between an object in orbit around a parent body. Clearly, DS1 (note no hyphen; Marc Rayman goes ballistic when people insert the dash) is not in orbit about Borrelly; it is only flying by, so the closest approach description is actually the correct one.
Alex R. Blackwell
University of Hawaii