Overview

• Penn State and NASA JPL researchers show most powerful uplinks track the ecliptic and are aimed at spacecraft near Mars, with transmissions clustered within about 5 degrees of Earth’s orbital plane.
• The team calculates a 77% chance an observer aligned with an Earth–Mars conjunction would sit in the path of a Deep Space Network transmission, compared with about 12% for other planet alignments and negligible odds otherwise.
• An average DSN signal is estimated to be detectable out to roughly 23 light-years with telescopes like ours, guiding searches toward nearby edge-on (transiting) exoplanet systems.
• Findings appear in The Astrophysical Journal Letters with an accompanying arXiv preprint, and the authors presented the results at the 2025 Penn State SETI Symposium.
• Follow-up will identify candidate star systems within the detection range, with the Nancy Grace Roman Space Telescope expected to expand suitable targets, while earlier alignment-based tests such as TRAPPIST-1 returned null results.