Hoenig elements/conjunction finding

Bill J Gray Aug 1, 2002

Roger, not sure where things went wrong, but here's a good check:
right-click on Hoenig and ask for "more info". The orbital elements
ought to show up roughly as follows:

Perihelion distance 0.7784940 AU
Orbital elements:
Eccentricity 1.0000000
Inclination of orbit 73.0668000 degrees
Argument of perihelion 105.7728000 degrees
Long. ascending node 321.0135000 degrees
Date of perihelion JD 2452549.49010 ( 1 Oct 2002 23:45:44.6)

I say "roughly" because the above elements come from the MPC site.
I went to

http://cfa-www.harvard.edu/iau/Ephemerides/Soft02.html

and downloaded the current comet elements, soft02cmt.txt. Then I
used "Extras... Add MPC Comets/Asteroids", and selected that file.
MPC has somewhat different elements from JPL, which may reflect MPC
having a few observations JPL lacks. (Or the other way around,
though I doubt this.)

The _Sky & Tel_ ephemeris may be based on a still shorter arc,
since I just got the above elements today. If so, you'll get a decent
match for "current" dates, slowly diverging as you go into the future.

Alex wrote:

"...I just want point out the Guide correctly find conjunctions for
the Moon and planets. And one could use conjunction menu again to find
the next conjunction and so on. But the next conjunction assumes will
occur on the next lunation so Guide is searching conjunction with
Moon's period. This is incorrect for conjunctions with satellites."

This is true. At present, Guide can find "next" and "previous"
conjunctions of the moon with slowly-moving objects (so that the "next
lunation" idea works) and conjunctions of inner planets with the sun
(which also occur at semi-regular intervals.)

But I've just given the matter a little more thought, and it seems
to me that I may be able to get all sorts of conjunctions working with
a better search routine. I will ponder this (unfortunately, I've got
a few other things going right now).

-- Bill