There is always something interesting happening in the sky. The Moon cycles through its phases and occasionally passes near a bright planet. Sometimes the Moon eclipses the Sun. And sometimes the Moon itself is eclipsed as it passes through Earth's shadow. The planets move against the stars and are most prominent at opposition (Mars, Jupiter and Saturn) or at greatest elongation (Mercury and Venus). Earth makes its annual orbit around the Sun and passes through its four seasons.
SKYCAL (Sky Events Calendar) will help you keep track of the sky by calculating the local date and time of all these celestial happenings. It displays them on a convenient calendar that you can print and hang on the wall. You can generate a calendar for a single month or for an entire year. Just choose your Time Zone.
To use SKYCAL, make your selections in three simple steps:
For time zones in North America and Europe, a Daylight Saving Time (DST) control appears that can be toggled on or off. In most of North America, DST is observed from the second Sunday of March through the first Sunday of November. In Europe, DST is called Summer Time (ST). ST is observed from the last Sunday of March through the last Sunday of Octomber. The initial settings of SKYCAL (Time Zone & DST) are based on the time zone setting in your computer's internal clock.
All sky events in section 2 are selected by default. Change them as needed. In Section 3, enter the year or year and month of your calendar. At present, SKYCAL works for all years from 1801 through 2100. This range will increase soon. You can select calendars other than the western Gregorian Calendar by clicking the Other Calendars button and choosing a calendar from the drop-down menu.
Besides the traditional 7-day per week calendar format, you can also display the sky events in a table (opened in a new window). This format shows additional information about many events because it has more room to display the extra data. The table can be printed and saved.
To learn more about SKYCAL, see About the Sky Events Calendar. Related links include:
Select Time Zone:
Use Daylight Saving Time (DST) for part of the year: Yes No
|Select Sky Events:
Calendar: Julian/Gregorian Calendar Other Calendar
Julian Day range: to
Week begins on: Sunday (Western) Monday (Latin/Asian) Saturday (Near Eastern)
Generate Sky Calendar:
Generate Sky Events Table:
All SKYCAL astronomical calculations are by Fred Espenak, and he assumes full responsibility for their accuracy. Special thanks to National Space Club summer intern Sumit Dutta for his valuable assistance in developing the Sky Events Calendar (July 2007).
Permission is freely granted to reproduce this data when accompanied by an acknowledgment:
"Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA's GSFC)"