#17 Date Change ⛵ 🌏 180th Meridian - Vertical Time
6 May 2026 · 54 min · 2K views · Océano Pacífico
What this video covers
Paula and Pedro aboard the Vuelta Vertical circumnavigation vessel cross the 180th meridian during a live session, triggering a date change that Paula explains in detail using a globe and hand-drawn diagrams.0:12 Sailing east at 9–11 knots, the boat had been advancing clocks by one hour for every 15 degrees of longitude traveled; crossing the antimeridian returned 12 hours at once, producing a week with two Saturdays and eight days. Paula explains why the International Date Line follows the 180th meridian rather than Greenwich — no major landmass crosses it — and why the line itself deviates from a straight meridian to keep island groups on the same calendar side. The boat carries two clocks: one fixed to UT, one adjusted to local solar time used for watches, meals, and sextant noon sights. The crew of seven is roughly at the halfway point of the ~40,000-mile Vuelta Vertical route; the leg from Chile to Alaska will be sailed by Paula and Pedro alone. Pedro announces that crew recruitment for the Northwest Passage will open soon, and a gathering is planned in Valdivia on 8 May, with a full circumnavigation presentation at the Encuentro de Navegantes in late November in Castellón.
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