PAGEOS, 18 October 1972
On the evening of 18 October 1972, led by Roy Cheesman, members of OASI were using the 26 cm refractor at Orwell Park when Janet Haywood noticed a moving point of light, subsequently identified as the artificial balloon-satellite PAGEOS (PAssive Geodetic Earth Orbiting Satellite). PAGEOS, launched by NASA on 24 June 1966, was a 30.5 m inflatable sphere, constructed from a highly reflective aluminized mylar film, intended to provide a tracking target for geodetic purposes. It remained in orbit for nine years.
The observers swung the telescope around and began to track PAGEOS. As it was moving across the sky at a considerable fraction of a degree per second, and the telescope is not easily manoeuverable, this was challenging! Roy Cheesman manned the finder telescope, two people wound the dome around, and other members took it in turns observing via the main telescope. Under both 30x and 250x magnification, PAGEOS was clearly visible as a white disk rather than a point of light.
PAGEOS (courtesy NASA).