Seven in the evening at the end of September, the last of the light going off the Maluti and the first cold of the night coming down into the Caledon valley. Khubetsoana is a suburb on the northern side of Maseru, ordinary houses and small shops, and on this particular Sunday a great many people in it were standing outside looking at the same thing.

What they saw, according to a report filed from Maseru the next morning, was a large white disc in the sky. Not a point of light: a disc, with a definite edge, and something like a star sitting in the middle of it. It stayed perfectly still for some minutes. Then it moved, quite quickly, a short hop northwards, what the writer estimated as about fifty metres, though it is hard to know what fifty metres means at an unknown distance. It stopped again. Then it set off north for good, in the direction of Butha-Buthe and the mountains, and as it went it shrank steadily until there was nothing left. The writer took the shrinking as proof of speed: it was not fading, it was leaving. Twenty minutes, roughly, from first sight to last.

The report adds that the same thing was seen all over South Africa that night, which, if it was, would put it in the same family as the country-crossing lights that turn up in this archive every few years and generally turn out to be a rocket. The archive has not found the South African press coverage to go with it. Perhaps it was there and the internet lost it. Perhaps Khubetsoana had the sky to itself.

Maseru had been here before. In January 2007 a resident wrote to the same reporting centre to say they had watched a large light with a trailing tail for nearly half an hour at dusk, hanging in the western sky and slowly descending until it went below the horizon, and had photographed it through a two-hundred-millimetre lens. The photographs were promised, and the report ends with the centre’s note left half-typed. The obvious candidate for a slow light with a tail low in the west at dusk in January is the planet Venus, or a jet contrail lit from below by a sun that has already set for the people on the ground. Both are very beautiful and both get reported often.

The white disc is harder. A bright planet does not look like a disc with a star inside it to an unaided eye, and does not hop. A high-altitude balloon, lit by a sun below the horizon, can look exactly like a large white disc hanging still, and can seem to jump when a gust takes it, and shrinks away as it drifts off downwind. Research balloons and weather balloons do drift over Lesotho. So, for that matter, does the moon, when it is behind thin cloud: a pale disc with a bright core. Except that on 29 September 2013 the moon was a waning crescent and did not rise until the small hours.

So: many people, one suburb, one disc, one hop, and a slow shrink towards the mountains. The Maluti have kept the rest.