Here are the applet source files:

• AboutSunClock.java - Information about the applet.
• Astro.java - A number of utilities for astronomical computation.
• AstroFormat.java - Utilities to display astronomical values.
• CityList.java - Manage the list of known cities.
• CityObject.java - The data that is known about each city.
• Constants.java - Constants used throughout the SunClock applet.
• Format.java - Convert numbers to visable text in a variety of formats.
• InfoDialog.java - Display the help dialog.
• Moon.java - Compute the moon rise and set times. Algorithms from "Astronomy on the Personal Computer."
• MoonPhase.java - Compute the phase of the moon. Based on algorithms in "Practical Astronomy With Your Calculator" and MoonTool Copyright © 1992 by John Walker. "The source code for Moontool is in the public domain. You are free to use it in any manner you wish."
• MoonPixels.java - Display the moon image with it's phase terminator.
• OptionDialog.java - Display the configuration dialog.
• OutlineComponent.java - Hierarchical lists are drawn here.
• OutlineDialog.java - A dialog that displays a hierarchical list. This is used for the InfoDialog (help class).
• OutlineElement.java - Data displayed in an OutlineComponent is stored in an OutlineElement.
• OutlinePanel.java - An OutlinePanel contains an OutlineComponent and its scroll bars. This is a workaround for problems using a ScrollPane to control an OutlineComponent.
• ParseParameter.java - Parse applet parameters.
• Sun.java - Compute the sunrise, sunset, and twilight times. This method is used to compute the times displayed in the text panel. Its accuracy is adequate for rising and setting phenomenon. Algorithms from "Astronomy on the Personal Computer."
• SunClockApplet.java - The applet itself: contains all user interaction.
• SunClock.java - Data is stored here (changing a value will awaken the data observers).
• SunClockDisplay.java - Container for all display panels.
• SunClockPanel.java - Textual information: sunrise, sunset, moon phase, location.
• SunrisePixels.java - Adjust the world map so it shows the sunrise/sunset terminator.
• EarthImage360.gif - World Map.
• FullMoon64.gif - Moon Image.
• DecClockTower.au - a recording of the clock tower at the (former) main office of Digital Equipment Corporation in Maynard, Massachusetts, which I heard daily for many pleasant years.

• The world map is distributed in the Macintosh Scrapbook and is copyright © Apple Computer Inc. Used by permission of Apple Computer Inc.
• The moon image was adapted from a photograph of a completely full moon taken, just before an eclipse, by Michael Myers and is used by permission of the photographer.

• The algorithms used to compute sun and moon data were adapted from "Astronomy on the Personal Computer."
• The low-precision computation of sunrise, sunset and twilight in SunrisePixels.java was adapted from The Explanatory Supplement to the Astronomical Almanac. The algorithm is also described on the USNO Time Services web page.
• The moon phase computation was adapted from a public-domain C implementation copyright © 1992 by John Walker and originally based on algorithms in "Practical Astronomy With Your Calculator."
• Astronomical utilities are from Astronomical Formulae for Calculators, Second Edition," "Practical Astronomy with Your Calculator" (3rd Edition), and "Astronomy on the Personal Computer".
• The algorithm used to locate an appropriate time zone is from from a Great Circle Computer web page developed by Steve Mitchell.
• The hierarchical list routines were adapted from an article in Java World, January 1997, and from my article in Apple's develop magazine issue 18, June 1994.
• Several of the utility routines were adapted from David M. Geary and Alan L. McClellan, "Graphic Java" ISBN 0-13-565847-0.
• You can get more information (and more accurate information) about timezones, sunrise, and moonrise times from the Directorate of Time at the United States Naval Observatory.

• When viewed from the Southern Hemisphere, the moon is upside down. I.e., when the moon looks like a D in the Northern Hemisphere, it looks like a C in the Southern Hemisphere. To fix this requires additional trignometry and knowledge of the sun's location.
• The display looks terrible on monochrome and gray-scale displays. This could easily be fixed if Java could tell applets more about their execution environment.

• "Astronomy on the Personal Computer." Oliver Montenbruck and Thomas Pfleger. Springer Verlag 1994. ISBN 3-540-57700-9.
• "The Explanatory Supplement to the Astronomical Almanac." P. Kenneth Seidelmann, Ed. ISBN 0-935702-68-7.
• "Practical Astronomy With Your Calculator." Patrick Duffett-Smith, Third Edition, Cambridge University Press, ISBN 0-521-35699-7.
• "Astronomical Formulae for Calculators, Second Edition." Jean Meeus. Willmann-Bell, Inc. 1982. ISBN 0-943396-01-8.
• The Web Page of The Directorate of Time at the United States Naval Observatory.
• John Walker's Web page.

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