THE COMET THAT CRUMBLED

Back in the early months of 2020, a comet - formally catalogued as C/2019 Y4 (ATLAS) – was beginning to brighten as it drew ever closer to the Sun. The headlines had all the usual excitable language you’d expect, while enthusiastic social media posts spoke of possible naked-eye wonders to come. Out in the depths of space, though, the icy wanderer had other ideas. As it raced towards the Sun, astronomers started to notice ominous changes in its appearance; rather than brightening steadily as it neared perihelion in May this year – when it would be at the closest point to the Sun in its orbit – the comet’s glow was faltering.

Soon, close-up images by astrophotographers showed the head of ATLAS – ordinarily where a solid, icy nucleus would hide among a shining cloud of gas and dust – was starting to elongate. The comet was falling to pieces. By 20 April, professional astronomers had pointed the orbiting eyes of the Hubble Space Telescope to the ensuing chaos, revealing