• What is T3 Project ? [Updated 2006 May. 24]
  • Observing Techinque [Updated 2006 May. 24]
  • What I do report? [Updated 2006 May. 24]
  • What happens if I found cometary feature ? [Updated 2006 May. 24]
  • Mailing List [Updated 2006 Sep. 14]
  • Observing Planner [Updated 2006 Nov. 15]


    This project is an observing program aim to the discovery of possible cometary features among asteroidal population having a Tisserand parameter respect to Jupiter (Tj) less than 3. T=3 is approximately the boundary between asteroidal and cometary orbits, according to Levison H. F., Comet Taxonomy, in Completing the Inventory of Solar System, ASP Conference Series Vol. 107, T. W. Rettig and J. M. Hahn eds. (1996). More info about T3 Project:

    Presentation at MACE 2006 (PDF file, 235 kB)

    Paper on Minor Planet Bulletin vol. 34 (PDF file, 100 kB) OBSERVING TECHNIQUE The strategy is quite simple: one have to image these minor planets (the complete list will be sent to the observers by the coordinator Luca Buzzi (usually once a week) in good seeing (for his location) and the resulting SNR of the stack must be at least 10, the more the better. With Astrometrica, one have to stack all the images according to the motion of the minor planet and then, if the cometary feature is not obvious, measure the SNR and above all the FWHM, which value must be at least 1.20-1.25 than that of the stars nearby (of similar SNR) for an hypothetical cometary feature. Example of FWHM data:
    asteroid 2005 SB216
    nearby star
    WHAT I DO REPORT ? Every observed object must be measured in the traditional way and sent to the MPC and sent to the coordinator. In the case a cometary feature is seen, indicating in the COM line of the header of the batch, the FWHM of the object relative to the stars and the SNR of the object. Also in the case that cometary feature is NOT seen, information must be sent to the coordinator with some comment about the observation. Example of report: COD 147 CON S. Foglia, C.Gariboldi 11, I-28100 Novara Veveri, Italy [s.foglia@libero.it] OBS D. Crespi, S. Foglia, G. Galli, S. Minuto MEA S. Foglia, G. Galli TEL 0.40-m f/4 reflector + CCD ACK 2005 SB216 cometary feature NET UCAC-2 COM FWHM = 4.0" SNR = 7.6 while stars FWHM = 2.8" K05SL6B C2005 12 29.78898 00 28 12.43 +14 26 54.0 18.9 147 WHAT HAPPENS IF I FOUND COMETARY FEATURE ? After that the rule of the coordinator is to inform the other component of the project for an indipendent confirmation of cometary feature and send a message to CBAT and MPC. The last step, once received some confirmation, is to inform some professional astronomers for the definitive report to the MPC. In the case of a discovery, in the IAUC will be comunicated the name of the discoverer of the cometary feature together with the names of the people who made the confirmation (on behalf of the "T3 project"). Example of result: IAUC 8668 - 2006 Feb 8 - COMET P/2005 SB216 (LONEOS)

    T3 MAILING LIST (by R. Behrend)

    This mailing list was founded with the claimed objective of making the communication between peoples involved in the t3-project easy and rapid. This mailing list is hosted at Geneva Observatory. Only peoples of the master list can send to- and receive messages from the list. The list is not moderated at all, so take a few minutes of reflection before hitting the send-icon. Actually, no archive is available. What can we do on t3@obs.unige.ch ? Well, one can discuss, between gentle(wo)men, of astronomy, astrophysics, image reduction techniques, telescopes, ccd-cameras, sciences including computer sciences, ask for help or post predictions, alerts, results, aso. The only condition is that it is not too far related to the t3-project and that it could be interresting to a significant part of the members

    OBSERVING PLANNER legend of the list sent to the observers by the coordinator