Post Encounter DSN Report
The Deep Space Network supported Deep Impact encounter operations for 10 days at "high readiness", from the beginning of encounter approach on June 26 through the look-back imaging on July 5.
The DSN delivered 99.3% of the downlinked data over the entire 10 days. This scores an A+ and was significantly higher than the DSN's guarantee of 95% return. Dr. Don Yeomans of the project's science team summed up the DSN's role, "We got all the data we could possibly ask for. The science team is ecstatic."
The pre-encounter telemetry stream was especially important as it carried the Optical Navigation images of the comet and its background star field. These images are used by the navigators to make the final course adjustment for the encounter.
The encounter telemetry was of keen interest to scientists and observers alike. During the five consecutive passes - lasting 44 hours - covering closest approach and impact, the DSN pulled in 100% of the spacecraft's telemetry. These included: the relayed approach images from the impactor, the increasingly detailed view of the comet, the images of the impact event and its evolution as the comet receded in view during look-back observations - all taken by the flyby spacecraft.
The spacecraft's ability to make observations exceeds the capability of its radio link, so recorded images and spectra were stored on-board and played back over several post-encounter passes.
This, for the DSN is part of the normal, solid job of connecting a deep space robotic explorer to its home planet and attendant team of scientists, engineers, and operators. Making that connection is usually not the front-page news of a space mission, especially when it goes well, but it's a critical part of space exploration. In spite of scoring a A+ job for Deep Impact, the demanding operations needed also exposed some fragility issues on DSN, which the DSN team managed to overcome through exemplary effort without impacting the mission.
The DSN team is proud to be part of the Deep Impact success.
Thanks to all of you at the Deep Space Network around the world. A mission can have a great encounter in space, but without the antennas of the DSN, and the return of the data to earth, the mission cannot be considered a success.