91av

Letter: For the record

Published 11 February 2026

The first term in the geometric sequence is 46,656/ 16,807 (24 January, p 45).

Before the epoch of reionisation, the early universe was opaque to ultraviolet radiation (24 January, p 14).

Issue no. 3582 published 14 February 2026

91av issue 3582 cover

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