2012/05/29 by H. Rampadarath, J. S. Morgan, S. J. Tingay +1 · 1 citation
Physics and Astronomy · #Baseline (sea) #Circumstellar habitable zone #Cosmology and Gravitation Theories #Interferometry #Noise (video) #Planet #Radio Astronomy Observations and Technology #Search for extraterrestrial intelligence #Space Science and Extraterrestrial Life #Very-long-baseline interferometry #astro-ph.EP #astro-ph.IM
paper · pdf · doi:10.1088/0004-6256/144/2/38
34 pages, 6 figures, 2 tables. Accepted on 25/05/2012 for publication in The Astronomical Journal
arxiv created 2012/05/29 · openalex publication_date 2012/06/28 · arxiv updated 2015/06/05 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The first Search for Extra-Terrestrial Intelligence (SETI) conducted with very long baseline interferometry (VLBI) is presented. By consideration of the basic principles of interferometry, we show that VLBI is efficient at discriminating between SETI signals and human generated radio frequency interference (RFI). The target for this study was the star Gliese 581, thought to have two planets within its habitable zone. On 2007 June 19, Gliese 581 was observed for 8 hr at 1230–1544 MHz with the Australian Long Baseline Array. The data set was searched for signals appearing on all interferometer baselines above five times the noise limit. A total of 222 potential SETI signals were detected and by using automated data analysis techniques were ruled out as originating from the Gliese 581 system. From our results we place an upper limit of 7 MW Hz −1 on the power output of any isotropic emitter located in the Gliese 581 system within this frequency range. This study shows that VLBI is ideal for targeted SETI including follow-up observations. The techniques presented are equally applicable to next-generation interferometers, such as the long baselines of the Square Kilometre Array.