Mercury's Sodium Tail and Pleiades cluster
author: Sebastian Voltmer/Novapix
reference: a-cnj01-30006
Image Size 300 DPI: 21 * 28 cm
Below the Pleiades star cluster is actually a planet: Mercury. Mercury's thin atmosphere contains small amounts of sodium that glow when excited by light from the Sun. Sunlight also liberates these atoms from Mercury's surface and pushes them away. The yellow glow from sodium, in particular, is relatively bright. Pictured, Mercury and its sodium tail are visible in a deep image taken on april 27 2022 from La Palma, Spain through a filter that primarily transmits yellow light emitted by sodium. First predicted in the 1980s, Mercury's tail was first discovered in 2001.