Hi Bill,

I realize this may not be the 100% appopriate forum for this, but since find_orb is available on the ProjectPluto website...

I tinker with find_orb from time to time have recently been following the orbit refinements of C/2013 A1 as new observations become available. C/2013 A1, of course, is the well-known "Mars Buzzer" which is expected to make a close pass to Mars in October 2014.

My questions:

1. when solving for C/2013 A1's orbit, there is a "Ma" value displayed - it this the expected distance in AU between the comet and the center of Mars? It appears to be about the right order of magnitude.

2. is there somewhere I can edit in Mars' orbital elements instead of Earth's to be able to spit the comet-planet MOID out in more detail?

Cheers,

Grant (who obviously has way too much time on his hands).