BETWEEN 2004 and 2021, American military pilots registered 144 reports of unidentified aerial phenomena (UAPs), the government’s po-faced term for UFOs. One turned out to be a large deflating balloon. The others are a mystery. So concluded a long-awaited report published on June 25th by the Office of the Director of National Intelligence (ODNI), which co-ordinates the work of American intelligence agencies. The nine-page “preliminary assessment” was the result of pressure from Congress. In June last year the Senate’s intelligence committee, then chaired by Marco Rubio, a Republican senator from Florida, asked the Department of Defence to create a UAP Task Force to streamline the collection of reports. In January it was given six months to publish its findings.

Some are striking. One is that UAPs “probably do represent physical objects”, rather than being technical anomalies or figments of pilots’ imaginations. That is because more than half the objects were registered across multiple sensors, including radar and infra-red. Moreover, 18 of the incidents suggested “unusual flight characteristics”, such as moving against the wind or manoeuvring abruptly, though the report warns that this could be the result of sensor errors or misperception.