Science Applications of Large Deep Space Network Arrays

The Deep Space Network (DSN) has begun work on vastly expanding its downlink capacity with the overall goal of increasing the telemetry data by about an order of magnitude every 10 years for the next 30 years. Large arrays of small antennas (several meters in diameter), operating at radio frequencies, are a leading technology being investigated to meet this goal. Large arrays promise more than just an increase in total ground aperture for reception of telemetry signals. They also could be used for direct scientific observations in the fields of radio astronomy, radar astronomy, and flight radio science, much like the single-aperture antennas of the DSN are now. In this context, large arrays have the potential to increase the signal-to-noise ratio of these observations and provide multiple, simultaneous beams and deep radio frequency images. As with the current DSN, science observations with large arrays could provide direct benefit to NASA projects as well as create avenues for the infusion of technology and techniques that enhance spacecraft tracking. This article examines the potential of large DSN arrays to enable new scientific observations and identifies key design issues of large arrays to maximize their potential for science in addition to their primary use for spacecraft tracking.