New! More Astronomy at Earth
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.
I would enjoy hearing what you think about Moon Calendar. Please write to me
at the address below.
Send comments and suggestions about Moon Calendar to Paul Carlisle
- The photograph of the Moon used in this program is courtesy of Michael Myers.
- The graphics correspond to the named lunar phases thus:
- Java won't let you print directly from an applet; if you want to print the
calendar, you can take a snapshot of your browser window, open the snapshot in
a paint program, and print from there. See your computer's documentation on
taking snapshots or printing the screen, and on working with graphics
- 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
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
- 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
Read about How Moon
Calendar was developed.
Moon Calendar has been visited times since December 8, 1997.
or are using an older browser. In any case, you can always see a complete list
of links on my Home
Page. If you have questions or comments about this site, please send me an