Science - Astronomy - Calendars and Timekeeping Islamic Calendar - Islamic months begin at sunset on the day of visual sighting of the lunar crescent. This site discusses the concept of the International Lunar Date Line and contains numerous maps of crescent visibility. Leap Seconds - 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 - Extensive descriptions of many astronomical time keeping systems, with information on time zones and Julian day numbers. The Calendar, Leap Years and the Year 2000 - An explanation of the calendar including the origin of the day, week, month and year. Calendar Conversions - A handy tool for converting to and from various calendars, including the Jewish calendar and the French Republican calendar. Time and Date - 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 - Information on date, time, and time zones from the New York Public Library. Lunisolar Calendar - 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. Blue Moon Myths - Second full moon in a month, or third full moon in a single season? Maya Calendar 2000 - 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. Britannica.com - Clockworks: From Sundials to the Atomic Second - Britannica.com explores the history of timekeeping, from sundials to cesium atomic clocks. Calendar Studies - 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. Indian Moons - A list of many American Indian tribe's names for months, days, and other calendar related information. LunarCal - A Perpetual Chinese Lunar Calendar - LunarCal is a 160-year perpetual Chinese Lunar Calendar for 1900 to 2060. Chinese festivals are listed and the moon phase is displayed. The Chinese Calendar - The mathematics of the Chinese calendar. Explains the rules for the Chinese calendar. The Islamic Calendar - The mathematics of the Islamic calendar in Singapore. The Difference Between the Millennium and Year 2000 - Questions and answers to satisfy the hearts of true millennium buffs. Calendars through the Ages - History and FAQs of calendars, from ancient Rome to outer space. Including Julian, Gregorian, Jewish, Islamic, Chinese, and Mayan. Annus Novus Decimal Calendar - A proposal for a non-sectarian, culturally neutral calendar system. Astronomy by JavaScript: Sun Calculators and More - Applets related to calendars and keeping time, including sidererial time. Calendrical Calculations - Published by Cambridge University Press. Gives a unified algorithmic presentation of the Gregorian, ISO, Julian, Coptic, Ethiopic, and Islamic civil calendars. Calendopaedia - The Encyclopaedia of Calendars. Month Calendar for Any Year - Create a calendar (requires JavaScript, does not work in Netscape 3). Month poetry, how the months got their names, day names in different languages, birthstones, gemstones, Roman gods and the blue moon. Sundials on the Internet - A major information source, with projects, detailed technical information, links to related sites, listings of societies. The North American Sundial Society - Includes general information, links, a register of dials in North America, and a message board. Analemmatic Sundials - Descriptions of these vertical post sundials, why they work, detailed account of the maths necessary to plot the hour lines. Sundials - A page from Jack Aubert, with technical information on construction and placing. Frans Maes' Sundial Site - A picture gallery of sundials collected by the author, with annotations and information on each. The majority are in Holland and Belgium. Also includes other information and links. The British Sundial Society - Information on the society, links, beginner's pages, including simple sundial patterns and templates, online facilities to calculate hour lines for different sundial types. The Dutch Sundial Society - Information is mostly in Dutch, but with some English language pages, including how to calculate several types of sundial. Sundials - Describes the history of sundials, and their development in Europe from the time of the Greeks. Includes literary and poetic references. Sundial Information - Describes sundial parts and names, the basic types, and has make your own pages for three simple types of dial. Cadrans Solaire - Describes different types of sundials, has other technical and general information. Offers free Shadows software to compute sundials of a number of different types for anywhere in the world. Phil's Sundial Photo Gallery - Includes British and international sundials with description and exact location; sun compasses. The Analemmatic Sundial - Describes design and construction of a six meter wide analemmatic sundial in Canada. Sundial Design Program - Software to design a vertical (wall mounting) sundial for walls that face up to 60 degrees away from due-south. netmation.com | netmation.net | netmation.org | netmation.tv Copyright © 1991-2005 Netmation Inc. All Rights ReservedSite Designed and Hosted by Netmation Inc.