The ^Minor Planet Center

(MPC)//xhttps://www.minorplanetcenter.net/cfa/ps/mpc.html^ and the

^IMCCE//xhttp://www.imcce.fr/fr^

provide orbital elements for comets. Guide updates its list of comets

using both sources; MPC gives currently-observable comets, IMCCE all

comets since about 1995. (Data for historical comets is already built

into the Guide DVD.) You can click on the following to download

some of these files, getting orbital data for newly-found objects and

improving orbits for already known objects. About 600 KBytes will be

downloaded.

^Click to download updated comet data and add it to Guide//dhttp://www.astro.vanbuitenen.nl/cometelements?format=guide soft02cm.txt;dhttps://www.projectpluto.com/eltdat.txteltdat.txt;a2789^  

Guide can also import other orbital elements if they're provided in

the "eight-line format", or the "one-line format" used for Daily Orbit

Updates. You wouldn't normally do this, but if you have generated an

orbit using Find_Orb, for example, you could import the resulting file

of orbital elements using the following command.

dhttps://www.minorplanetcenter.net/iau/Ephemerides/Comets/Soft02Cmt.txt soft02cm.txt

^Add MPC asteroids/comets//!2052^