- Leap Seconds - http://tycho.usno.navy.mil/leapsec.html
Civil time is occasionally adjusted by one second increments called leap seconds. A detailed explanation of what a second actually is, and why leap seconds are necessary.
- Astronomical Time Keeping - http://www.maa.mhn.de/Scholar/times.html
Extensive descriptions of many astronomical time keeping systems, with information on time zones and Julian day numbers.
- Time and Date - http://www.timeanddate.com/
Lots of time and date related information, such as yearly and monthly calendars, counters, countdown, and the world clock which shows the current time in cities all over the world.
- Time and Dates - http://www.circ.uab.edu/nypldr/1time/index.htm
Information on date, time, and time zones from the New York Public Library.
- Blue Moon Myths - http://www.infoplease.com/spot/bluemoon1.html
Second full moon in a month, or third full moon in a single season?
- Maya Calendar 2000 - http://mayacalendar.com
The calendar was the center of Maya life and their greatest cultural achievement. To carry out their astronomical calculations they developed a sophisticated mathematical system. The Maya Calendar website is developing with the intent of providing a complete view of Maya culture.
- Calendar Studies - http://hermetic.nofadz.com/cal_stud.htm
Articles on the Gregorian and Julian calendars, the ISO date format, the Julian day number system, the Maya calendar, the Goddess lunar calendar, the Liberalia Triday Calendar and C functions for date conversion; plus software for calendrical conversion.
- The Chinese Calendar - http://www.math.nus.edu.sg/aslaksen/calendar/chinese.shtml
The mathematics of the Chinese calendar. Explains the rules for the Chinese calendar.
- The Islamic Calendar - http://www.math.nus.edu.sg/aslaksen/calendar/islamic.shtml
The mathematics of the Islamic calendar in Singapore.
- Calendars through the Ages - http://webexhibits.org/calendars/
History and FAQs of calendars, from ancient Rome to outer space. Including Julian, Gregorian, Jewish, Islamic, Chinese, and Mayan.
- Calendrical Calculations - http://emr.cs.uiuc.edu/home/reingold/calendar-book/index.shtml
Published by Cambridge University Press. Gives a unified algorithmic presentation of the Gregorian, ISO, Julian, Coptic, Ethiopic, and Islamic civil calendars.
- Calendopaedia - http://www.geocities.com/calendopaedia/
The Encyclopaedia of Calendars.
- Millennium Mistake - http://www.millenniummistake.net/
Explains the difference between millenium and year 2000 as the absence of a year zero.
- Rosetta Calendar - http://rosettacalendar.com/
An online handy tool for converting to and from the Gregorian, Julian and Jewish calendars.
- Indian Moons - http://www.americanindian.net/moons.html
A list of many American Indian tribe's names for months, days, and other calendar related information.
- Astro Portal - CalSKY - http://www.calsky.com/
The worldwide interactive online astronomical/space calendar and calculator - for friends of astronomy, as well as astronomers.
- Lunisolar Calendar - http://www.pburch.net/lunarcal.html
Lunar calendar with lunations, from new moon to new moon, instead of months. Moon phase on each day. Chinese, Jewish, and Islamic months. Eclipses, meteors, planets, star charts. Christian, Pagan, Islamic, Hindu, and Jewish holidays.
- World Holidays: Weeks and Months - http://www.gkindia.com/holidays/weekdays.htm
Information on the origin of the week, and etymology of month and weekday names.
- The Julian and Gregorian Calendars - http://www.hermetic.ch/cal_stud/cal_art.html
Explanations of the Julian Calendar, the Gregorian Reform, the adoption of the Gregorian Calendar, the length of the tropical year and related matters.
- Julian Day Numbers - http://www.hermetic.ch/cal_stud/jdn.htm
An explanation of the Julian day number system used by astronomers and calendricists.
- Types of Calendars - http://www.hermetic.ch/cal_stud/lunarcal/types.htm
An explanation of lunar, solar, lunisolar, rule-based and other types of calendars.
- ACalendar.com - http://www.acalendar.com/
The calendar has many options with a standard monthly interface, including: Sunrise Sunset, Moon phases and much more.
|
