DSES Investigation of opportunities for radio source occultations by Comets Machholz C/2004 Q2 and 9/P Temple 1
and observations of the Deep Impact encounter with 9/P Temple 1

This project took place in the first half of 2005 and was motivated by the opportunities to observe comet Machholz C/2004 Q2 in January 2005 and by the encounter of 9P/Tempel 1 with the Deep Impact mission impactor on July 4, 2005. The initial goal of our project was to observe occultations of radio sources that might lie behind the trajectory traversed by the comets as seen from the DSES antenna site, and to measure the absorption at hydrogen and hydroxyl frequencies during the occultation. As comets approach the Sun their comas expand thus providing a bigger target and greater opportunity for an occultation.

After comparing the comet trajectories as seen from the DSES antenna site with a catalog of radio sources from Jim Sky it was determined there were no suitably located radio sources that would permit an occultation observation. So instead we shifted our efforts to observing and recording the Deep Impact encounter with 9/P Tempel 1 at the H1 frequency for whatever there might be to be seen. Although a cloud of water vapor was predicted to result from the impact, our efforts to observe it were hampered by the fact that there was no suitably bright radio illumination source behind the event. Nevertheless, preparation for the even served to perfect our receiving equipment and tracking capabilities and techniques.

The results of this effort are presented in the following activity report:

  • 07/12/05 Deep Impact Tracking - Final Report

The project resulted in our making many improvements in our equipment, tracking system and techniques for making occultation observations and we hope to apply them should future comets present occultation opportunities.

The plots of the comets listed below were generated using Radio Eyes and show their paths against the background of radio sources (green) and pulsars (yellow) as seen from the DSES antenna site. See the animations below for the Comet-Sun distances for the dates shown in these plots.

Tracking Data Trajectory Animations

The orbits for Deep Impact, 9P/Tempel 1, Comet Machholz C/2004 Q2 shown in the plots below are updated daily. Click the plots to view Quicktime animations showing their positions for the period Apr 4, 2004 to Apr 4, 2006.

View looking down on the north pole of the Sun
 
View from 15 degrees above the ecliptic

Deep Impact Websites

Last update: Monday, 06-Mar-2006 10:13:26 PST by Webmaster