Office of the Secretary of Defense

The Office of the Secretary of Defense (OSD) is a U.S. Department of Defense administrative office established to support the Secretary of Defense. Within OSD, the All-domain Anomaly Resolution Office (AARO) was officially established in 2022 under the National Defense Authorization Act to investigate unidentified anomalous phenomena (UAP) across air, sea, space, and land domains. AARO investigates reports of unexplained aerial phenomena and coordinates efforts across the Department of Defense and federal agencies. As of 2022, AARO had reviewed over 500 UAP reports dating back to 2004, with 143 of 144 objects from 2004-2021 remaining unidentified. AARO has consistently found no evidence of extraterrestrial activity or recovered alien technology. The office maintains an expanding caseload, with over 750 new UAP sightings reported between May 2023 and June 2024.