月距法による時刻推定- 間接測定による方法の実海域での検証 -

URI http://harp.lib.hiroshima-u.ac.jp/jcga/metadata/12089
File
Title
月距法による時刻推定- 間接測定による方法の実海域での検証 -
Title Alternative
Time Determination by Lunar Distance Method - Indirect Measuring of Lunar Distance and Verification on Actual Ocean Voyage -
Author
氏名 田中 隆博
ヨミ タナカ タカヒロ
別名 Tanaka Takahiro
氏名 小林 拓司
ヨミ コバヤシ タクジ
別名 Kobayashi Takuji
氏名 島村 圭一
ヨミ シマムラ ケイイチ
別名 Shimamura Keiichi
Subject
Lunar Distance Method
Celestial Navigation
Abstract

There was no way to know the error of clock once the ship sailed out into the ocean before the invention of marine chronometer. The navigator asked for the answer into the movement of heavenly bodies. The moon travels about 0.55 degree per hour, roughly equivalent to its own apparent diameter, against the celestial coordinate. Consequently, the angle between the moon and other celestial bodies, the angles called “the Lunar Distance”, changes from moment to moment. It can determine the time by measuring the Lunar Distance and comparing the distance with forecasted values on the almanac. However, to measure the Lunar Distance by sextant on the ship is very difficult, good results have not been raised with the classical Lunar Distance method.
In this paper, in order to overcome the difficulty of measuring the Lunar Distance, we showed the method which is able to measure the Lunar Distance indirectly. We actually performed the indirect measuring method on the ocean voyage and show some results.

Journal Title
海上保安大学校研究報告, 理工学系
Volume
56
Issue
1-2
Spage
11
Epage
17
Published Date
2013-03-29
Publisher
海上保安大学校
ISSN
0287-2951
NCID
AN10088865
Self DOI
Language
jpn
NIIType
Departmental Bulletin Paper
Text Version
出版社版
Sort Key
02
Old URI
Set
jcga