NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Ted Gerrard
Date: 2007 Nov 15, 16:48 -0000
Google Earth
Those of you who have access to Google Earth might care to try out their navigation skills. On 25th April, 1700 Edmond Halley's ship anchored in the bay to the southwest of the Atlantic Island of Trinidade before Halley landed and claimed the island for King William III.
The place close to where Paramore dropped anchor is (co-incidentally) marked with a blue spot on the Google map. Halley placed the island as being at 29.50W and between 20.25 and 20.29S by measuring the moon's position amongst the Hyades cluster 4 days earlier (longitude + DR) and a noon sun fix on arrival, the sun being at an altitude of 56 degrees.
Zooming in on the island one can even identify exactly where Halley landed and the rocky gully where his crew replenished their water supplies. Try as I might I could not locate the descendants of the goats and pigs he left behind.
This positional fix (some 30 minutes of longitude in error and more or less spot on latitudinally) must surely rate as one of the most remarkable navigational achievements of all time.
One wonders what Halley (or Newton) would have made of Google Earth?
Warning. If you type Trinidade in the Google search you will finish up in the middle of Brazil.
Ted Gerrard
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to NavList@fer3.com
To , send email to NavList-@fer3.com
-~----------~----~----~----~------~----~------~--~---