Sir

I agree with Michael M. Shara and colleagues (Nature 446, 159–162; 2007) that the star Z Camelopardalis was a classical nova a few thousand years ago. In fact, a record of the eruption exists in Chinese documents of the time. There was, apparently, a report of a 'guest star' in October–November 77 BC (P. Y. Ho Vistas Astron. 5, 127–225; 1962). The position in the sky fits Z Camelopardalis. This seems to be the oldest classical nova recorded in any surviving text.