OSA's Digital Library

Journal of the Optical Society of America

Journal of the Optical Society of America

  • Vol. 23, Iss. 4 — Apr. 1, 1933
  • pp: 143–147

Experiments with the Bubble Sextant at Sea

E. O. HULBURT  »View Author Affiliations


JOSA, Vol. 23, Issue 4, pp. 143-147 (1933)
http://dx.doi.org/10.1364/JOSA.23.000143


View Full Text Article

Acrobat PDF (735 KB)





Browse Journals / Lookup Meetings

Browse by Journal and Year


   


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools

Share
Citations

Abstract

Altitudes of celestial objects were observed with the bubble sextant from a 950 ton ship and a 12 ton craft at sea. For moderate sea conditions individual altitudes were occasionally as much as 60 minutes of arc in error and averages of 5 consecutive observations were usually correct within 30 minutes of arc. On the 950 ton ship a portion of the error was due to the vibration of the ship caused by wind, engines, etc., and a larger portion was due to the horizontal acceleration arising from the roll and pitch of the ship. If the roll were simple harmonic the latter error could be partially eliminated by taking the sextant altitude at the midpoint of the roll. A small pendulum device was arranged to sound a buzzer signal at the midpoint of the roll and the sextant observations were made simultaneously with the buzzer signal. This improved the accuracy of the bubble sextant altitudes by roughly a factor of 2, so that individual observations were rarely more than 30 minutes of arc in error and averages of 5 consecutive altitudes were usually correct within 15 minutes of arc for a moderate sea.

Citation
E. O. HULBURT, "Experiments with the Bubble Sextant at Sea," J. Opt. Soc. Am. 23, 143-147 (1933)
http://www.opticsinfobase.org/josa/abstract.cfm?URI=josa-23-4-143


Sort:  Journal  |  Reset

References

  1. Descriptions of and experiments with artificial horizon sextants, mostly from the standpoint of aerial navigation, are given by Eaton, Report No. 131, 1922, and Beij, Report No. 198, 1924, Nat. Advisory Committee for Aeronautics; H. N. Russell, Proc. Ast. Soc. Pacific 31, 129 (1919); Gatty, Jr. Soc. Aut. Eng. 30, 153 (1932).
  2. Kaster, Proc. U. S. Inst. Naval Eng. 56, 607 (1930).

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited