Using Polaris and the Big Dipper to approximate local standard time

Edwin H. Kaufman Jr, Corey R. Page, Casey R. Watson

Department of Mathematics, Central Michigan University, Mount Pleasant, USA;.
Department of Mechanics, Materials, and Aerospace Engineering, Illinois Institute of Technology, Chicago, USA.
Department of Physics and Astronomy, Millikin University, Decatur, USA.

DOI: 10.4236/ns.2012.412133                

Abstract

In this paper we introduce methods for approximating local standard time in the Northern Hemisphere using Polaris and the Big Dipper as well as alternative reference stars, and describe in detail how to construct a device we call a dipperclock to facilitate this process. An alternative method which does not require a dipperclock is also discussed. Ways of constructing dipperclocks which glow in the dark are presented. The accuracy of dipperclocks is examined, both theoretically and through field testing. A java program is provided for creating dipperclocks customized to a particular year-long time period and place to get improved accuracy. Basic astronomical definitions and justifications of the results are provided. We also discuss the use of dipperclocks to find longitude and latitude.

Keywords

Polaris; Big Dipper; Time; Longitude; Latitude

Conflicts of Interest

The authors declare no conflicts of interest.

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