The Challenger Expedition: Exploring the Ocean's Depths Collection_Time and the Prime Meridian I did choose to focus

I did choose to focus stack this image to get the most from the foreground elements

We were lucky

tropic lines

Measuring a generous 38 x 42cm

during the day or the night and to find the time and length of both sunrise and sunset

The Challenger Expedition: Exploring the Ocean's Depths Collection_Time and the Prime Meridian I did choose to focusThe Challenger Expedition: Exploring the Ocean's Depths is the story of the groundbreaking scientific ocean study by HMS Challenger in 1872 that transformed our understanding of the deep sea. Published to mark the 150th anniversary of its launch. Discover our full range of Royal Museums Greenwich publications.