Backstaff
id:
backstaff-251-17315806
title:
Backstaff
text:
The backstaff is a navigational instrument that was used to measure the altitude of a celestial body, in particular the Sun or Moon. When observing the Sun, users kept the Sun to their back and observed the shadow cast by the upper vane on a horizon vane. It was invented by the English navigator John Davis, who described it in his book Seaman's Secrets in 1594.
brand slug:
wiki
category slug:
encyclopedia
description:
Navigational instrument
original url:
https://en.wikipedia.org/wiki/Backstaff
date created:
date modified:
2023-10-08T20:41:56Z
main entity:
{"identifier":"Q3298443","url":"https://www.wikidata.org/entity/Q3298443"}
image:
fields total:
13
integrity:
14