The Phoenix search results at Parkes

Abstract

For 16 weeks (February to June of 1995), Project Phoenix had the exclusive use of the 64 m Parkes radio telescope in New South Wales, Australia, as well as another element of the Australian Telescope National Facility (ATNF), the 22 m Mopra telescope, 200 km to the north at Coonabarabran. With these two telescopes, we conducted a targeted search of nearly two hundred solar-type stars covering the frequency range from 1.2–3 GHz. The signal detection system described in the paper by Dreher [1]was optimized to detect narrowband signals (presumed to be transmitted by another technological civilization) originating in the vicinity of these targets. The system was sensitive to signals that were continuously present, or pulsed regularly, even if their frequencies drifted, or changed slowly in time. Many signals of precisely this nature were detected—coming from our own technology! All manner of transmitters, from microwave ovens to satellite downlinks, are rapidly making this naturally quiet portion of the electromagnetic spectrum extremely noisy. The use of the two widely separated telescopes as a pseudo-interferometer was essential to discriminate against signals of terrestrial origin. The performance of the system and the results of the observing campaign are presented in this paper, while the cooperative science observations that were undertaken with Australian PIs are described in a companion paper.