The Karl G. Jansky Very Large Array (VLA), located on the Plains of San Agustin in New Mexico, is one of the world’s most powerful and versatile radio telescopes. Rather than a single dish, the VLA consists of 27 individual antennas spread across many kilometers, working together as a single instrument. This design allows it to detect extremely faint radio signals and to pinpoint their locations on the sky with remarkable precision. Because the antennas can be moved into different configurations, the VLA can be used to study everything from nearby planets to distant galaxies. Its flexibility and sensitivity make it an ideal facility for searching for technosignatures, radio signals that could indicate the presence of advanced technology elsewhere in the Universe.
In this work, Breakthrough Listen collaborates with the SETI Institute to use the VLA in a new way through a custom-built system called COSMIC (Commensal Open-Source Multimode Interferometer Cluster). COSMIC allows us to obtain a copy of the data while the VLA carries out its normal astronomical observations, dramatically increasing the amount of sky that can be searched without interfering with other science. COSMIC processes enormous volumes of data in real time, filters out interference from Earth’s own technology, and searches for extremely narrow radio signals that stand out from natural cosmic noise. This approach has enabled one of the largest and most systematic technosignature searches ever conducted with the VLA, while also creating a rich public data set that can be revisited as new analysis techniques are developed.