Moon Calendar was written primarily for elementary school students. It shows the phases of the Moon for each day of a selected month.

You can set the calendar to any date from 3999 BC to 3999 AD. Note that the calendar does not have a year 0; this corresponds to the year 1 BC.

Clicking any day cell on the calendar will take you to a screen presenting a more detailed view of the moon on that day, along with other information about the Sun and Moon.

The "Information" button will present an overview of Moon Calendar. On this screen, you will also find links to other sites related to the Moon.

Clicking on any text on a dark gray background will bring up a more detailed explanation of that item.

We would enjoy hearing what you think about Moon Calendar. Please write to us at the address below.

Please be patient - Moon Calendar will take a minute or two to download and start.

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You must have a Java capable browser to use Moon Calendar.

• Moon Calendar's display of the Moon has North at the top of the picture, and East at the left. This is the way the Moon "normally" looks, for an observer in the Northern Hemisphere. We apologize for being inconsiderate to those people who live South of the equator; we are working to correct this hemicentrism, and will eventually have Moon Calendar "flip" the image when the equator is crossed.

• Moon Calendar currently uses rather approximate methods to determine the position of the Sun and Moon, and their rise and set times. Accuracy will be improved in a future version. For now, however, you can expect the times to be within about 5 minutes of their actual values for the Sun, while the values for the Moon may be off by nearly 45 minutes.

• If you get bad rising and setting times for the Sun or Moon, your computer may not be set to the proper time, date, or location. Moon Calendar reads your system's information to determine how to set the time, and what time zone you are in.

  On some computers, the time zone information is not available. In this case, times are reported in Greenwich Mean Time. Set the Longitude to zero; this will give times that are close to those for your time zone.

• Moon Calendar defaults to Latitude 42 degrees North, Longitude 83 degrees West. This is the location of Detroit, Michigan, where the author lives. If you choose "Reset to Current," the location settings will revert to this value.

• Not all browsers display Moon Calendar the same way. We feel that Moon calendar looks best when viewed with Netscape Communicator 4 under Windows 95, or Microsoft Internet Explorer under Macintosh OS 8.

• The scrolling text panel on the "help" screen sometimes doesn't reset properly. Try scrolling all the way to the bottom, then all the way to the top. This usually resets the display.

• Sometimes the screen doesn't redraw properly. If this happens, resize your browser window slightly. This forces the screen to redraw itself again.

• Currently, if you are near the extremes allowed for the date range, the program will stop if the range is exceeded. Reset the time or date to resume normal operation.

Read about How Moon Calendar was developed.