Radio Source Occultations by Comets

A potential capability of the DSES radio dishes is to observe the occultation of radio sources by passing comets. As comets approach the Sun their comas expand thus providing a larger target and increased likelyhood that an occultation will occur. Such events although rare, would permit us to measure the absorption at hydrogen or hydroxyl frequencies during the occultation of the radio source behind it.

During 2005, flybys of comet Machholz (C/2004 Q2) and 9/P Temple 1 presented possibilities for such experiments as did the encounter of the Deep Impact impactor with 9/P Temple 1. Details of our efforts to find occultation opportunities and to observe the Deep Impact encounter are can be found here.