SETI Optical Search Expansion
SETI has evolved to optical searches with the Vera Rubin Observatory planned to scan 10-20 billion stars for technosignatures. This represents a major shift from traditional radio-based searches to complement existing detection methods.
- The concept of searching for laser signals is not new; it was first proposed by Nobel laureate Charles Townes and R. N. Schwartz in 1961, shortly after the laser's invention. For decades, however, searches focused on radio waves because the technology was more mature. - The Vera C. Rubin Observatory will conduct the Legacy Survey of Space and Time (LSST), a 10-year mission to image the entire southern sky every few nights with the world's largest digital camera. This survey is expected to generate about 20 terabytes of data every night. - Optical SETI primarily looks for technosignatures in the form of brief, powerful flashes of monochromatic (single-color) light. A powerful laser could theoretically appear thousands of times brighter than its parent star for a short duration. - A major advantage of optical signals over radio is their ability to carry far more information due to higher bandwidth, the same principle behind the use of fiber optics for internet on Earth. - While the Rubin Observatory's primary goals are to study dark matter and map the solar system, its rapid, repetitive scanning of the sky is uniquely suited for detecting transient events like potential extraterrestrial laser signals. - Other dedicated optical searches are also active, such as the SETI Institute's LaserSETI program, which is deploying a network of instruments designed to monitor the entire night sky continuously. - The $100 million Breakthrough Listen initiative also has a dedicated optical search component using the Automated Planet Finder telescope at Lick Observatory. It is sensitive enough to spot a 100-watt laser from over 4 light-years away.
