The SETI program has launched an extensive survey using the Allen Telescope Array (ATA) to search for technosignatures. Researchers are focusing on the direction from which an observer could view Earth transiting the Sun, a concept based on the game theory principle of a Schelling point. This campaign marks the first systematic observation of the anti-solar point.
The ATA operates within a frequency range of 2356–3700 MHz, utilizing 28 antennas, each 6.1 meters in diameter. The system employs a dual-beam mode to isolate signals and identify their origin. Algorithms scan for narrowband signals with Doppler drift, comparing data between beams to filter out terrestrial radio interference. Experts manually classify the remaining spectrograms.
As of September 12, the project had covered 12% of the ecliptic plane, collecting 1.3 petabytes of data over 126 sessions and 131 nights. Analysis of 67% of the data yielded nearly 170 million initial signals, with over 11,000 spectrograms selected for visual review. Among 8,473 cataloged items, 25 signals showed higher intensity in the target beam.
These 25 signals, detected across 10 frequencies and 10 coordinates over 7 nights, are currently classified as candidates for further investigation. Researchers plan to re-observe these coordinates to determine if the signals persist or are merely terrestrial interference. The full survey is expected to span over 4 years, requiring more than 700 sessions and 11 petabytes of data.
