The interstellar object 3I/ATLAS, discovered on July 1, 2025, shows no evidence of being anything other than a natural object. Because interstellar visitors are extremely rare, the Breakthrough Listen Initiative and its partners conducted extensive observations shortly after discovery and through its close approach to Earth.

Radio searches using the Allen Telescope Array covered 1–9 GHz and found no technosignatures. MeerKAT detected natural hydroxyl emission from cometary activity and, using BLUSE, ruled out artificial signals down to 0.17 W across 900–1670 MHz. The Vera C. Rubin Observatory and additional optical and infrared spectroscopy detected no artificial optical or laser emissions.

Further radio studies were carried out with the Parkes Murriyang telescope across several 2025 sessions, reaching sensitivities of roughly 5 W, and with the Green Bank Telescope at closest approach, achieving 0.1 W sensitivity – the most sensitive search to date – with no artificial emissions detected.

All data appear consistent with natural comet-like behavior. However, due to the rarity and scientific importance of interstellar objects, monitoring will continue as part of a broader, highly sensitive search for technosignatures. Publicly accessible datasets and analysis tools such as blimpy and turboSETI support ongoing community research.

For more detalized information about the telescopes involved in the research, and the results, read the original article by Oxford University/SETI Institute.