CFUAP - COMET Follow Up Astrometric Program

1. Introduction

Astrometry of comets give us the opportunity to improve their orbital elements.
It seems that there are always too many unnecessary observations of comets 
(the easy, bright ones, in convenient parts of the sky), and few, if any,
of what really needed to improve their orbits.

To avoid this problem we would like to propose an observational's program
called Comet Follow Up Astrometric Program (CFUAP).

2. CFUAP observing program

CFUAP is based on MPC information about comets such as the comet.dat file
and the "Dates Of Last Observation Of Comets" page.

Observational's opportunities are grouped as follow:

1) preliminary orbit (e=1):   comets having eccentricity forced to 1 in their preliminar orbit (designation sequence)

2) unperturbed orbit:         comets having unperturbed orbital elements (designation sequence)

3) other long period comets:  long period comets in order of date of last observations

4) other periodic comets:     periodic comets in order of last observed period

5) comets with Pdisru > 0.4:  Nearly Isotropic comets with Probability of Disruption [2] greater than 40% (Pdisr sequence)

observations of comets reported in the groups 1) and 2) will appear in a dedicate MPECs while comets listed in gruop 3) are included in
the Observations of Comets MPECs except for the recovery of unnumbered period comets.

3. CFUAP Service

CFUAP service will be upgraded the day after the issue of MPECs about comets.

or each object the following information are reported:
Comet              comet's name 
PeriDate           date of Perihelion
Last Obs           date of last observation
Magn.              magnitude of last observation
Code               observatory code of the last observation
q                  perihleion distance in A.U.
e                  eccentricity
i                  inclination in degrees
Tj                 Tisserand parameter respect to Jupiter
classification     classification scheme according to [1]:

Tj < 2Nearly Isotropic (NI)a > 10000 AUNew
a < 10000 AUReturning (Ret)a > 40 AUExternal (Ext)
a > 40 AUHalle Type (HT)
2 < Tj < 4 or Tj > 4 and a < aJEcliptic (Ecl)Tj < 3Jupiter Family (JF)
Tj > 3 and a > aJChiron Type (Chi)
Tj > 3 and a < aJInner Solar System (ISS)q < 1.3 AUNear Earth Object (NEO)
q < 1.665 AUMars Crosser Object (MC)
q > 1.665 AUMain Belt Region (MBR)a < 2.1 AUHungaria (Hun)
q > 1.665 AUMain Belt Region (MBR)2.1 < a < 3.7 AUMain Belt (MB)
q > 1.665 AUMain Belt Region (MBR)3.7 < a < 4.1 AUHilda (Hil)
q > 1.665 AUMain Belt Region (MBR)a > 4.1 AUThule (Thu)
Tj > 4 AND a > aJTrans-Neptunian (TNO)a < 50 AUEKBO
a > 50 AUScattered Disk (SD)
aJ = Jupiter's semimajor axis a = comet's semimajor axis For groups 3 and 4 also the UnObs is reported: for long period comets it is the unobserved days while for periodic comets it is the unobserved apparitions. 4. Note [1] Dynamical Taxonomy of Solar system bodies (Masi and Foglia, in preparation) [2] Comet disruption: a statistical approach for the nearly isotropic comets (Masi and Foglia, Journal of the British Astronomical Association, vol.119, no.4, p.203-204, 08/2009)
Last Update 2006 Nov 27


Gianluca Masi
Sergio Foglia