Time

Measuring Time

The liger is the offspring of a lion and a tigress, whereas the tigon is the result of mating a tiger with a lioness. Both are zoo-bred hybrids, and it is probable that neither occurs in the wild, as differences in the behavior and habitat of the lion and tiger make interbreeding unlikely. The liger and the tigon possess features of both parents, in variable proportions, but are generally larger and darker than either.

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Also called summer time, daylight saving time is a system for uniformly advancing clocks, especially in summer, so as to extend daylight hours during conventional waking time. In the Northern Hemisphere, clocks are usually set ahead one hour in late March or in April and are set back one hour in late September or in October; most Southern Hemisphere countries that observe daylight saving time set clocks ahead in October or November and reset them in March or April. Equatorial countries do not observe daylight saving time because daylight hours stay about the same from season to season in the lower latitudes.

The practice was first suggested in a whimsical essay by Benjamin Franklin in 1784. In 1907 an Englishman, William Willett, campaigned for setting the clock ahead by 80 minutes in four moves of 20 minutes each during the spring and summer months. In 1908 the British House of Commons rejected a bill to advance the clock by one hour in the spring and return to Greenwich Mean (standard) Time in the autumn.

Several countries, including Australia, Great Britain, Germany, and the United States, adopted summer daylight saving time during World War I to conserve fuel by reducing the need for artificial light. During World War II, clocks were kept continuously advanced by an hour in some nations—for instance, in the US from 9 Feb 1942 to 30 Sep 1945—and England used “double summer time” during part of the year, advancing clocks two hours from the standard time during the summer and one hour during the winter months.

In 2005 the US Congress changed the law governing daylight saving time, moving the start of daylight saving time from the first Sunday in April to the second Sunday in March, while moving the end date from the last Sunday in October to the first Sunday in November starting in 2007. In most of the countries of Western Europe, daylight saving time starts on the last Sunday in March and ends on the last Sunday in October.

Julian and Gregorian Calendars

The Julian calendar, also called the Old Style calendar, is a dating system established by Julius Caesar as a reform of the Roman republican calendar. Caesar, advised by the Alexandrian astronomer Sosigenes, made the new calendar solar, not lunar, and he took the length of the solar year as 365% days. The year was divided into 12 months, all of which had either 30 or 31 days except February, which contained 28 days in common (365-day) years and 29 in every fourth year (a leap year, of 366 days). Because of misunderstandings, the calendar was not established in smooth operation until ad 8. Further, Sosigenes had overestimated the length of the year by 11 minutes 14 seconds, and by the mid-1500s, the cumulative effect of this error had shifted the dates of the seasons by about 10 days from Caesar’s time.

This inaccuracy led Pope Gregory XIII to reform the Julian calendar. His Gregorian calendar, also called the New Style calendar, is still in general use. Gregory’s proclamation in 1582 restored the calendar to the seasonal dates of ad 325, an adjustment of 10 days. Although the amount of regression was some 14 days by Pope Gregory’s time, Gregory based his reform on restoration of the vernal equinox, then falling on 11 March, to the date (21 March) it had in ad 325, the time of the Council of Nicaea. Advancing the calendar 10 days after 4 Oct 1582, the day following being reckoned as 15 October, effected the change.

The Gregorian calendar differs from the Julian only in that no century year is a leap year unless it is exactly divisible by 400 (e.g., 1600, 2000). A further refinement, the designation of years evenly divisible by 4,000 as common (not leap) years, will keep the Gregorian calendar accurate to within one day in 20,000 years.

Jewish Calendar

The Jewish calendar is lunisolar—i.e., regulated by the positions of both the Moon and the Sun. It consists usually of 12 alternating lunar months of 29 and 30 days each (except for Heshvan and Kislev, which sometimes have either 29 or 30 days), and totals 353, 354, or 355 days per year. The average lunar year (354 days) is adjusted to the solar year (365% days) by the periodic introduction of leap years in order to assure that the major festivals fall in their proper season. The leap year consists of an additional 30-day month called First Adar, which always precedes the month of (Second) Adar. (During leap year, the Adar holidays are postponed to Second Adar.) A leap year consists of either 383, 384, or 385 days and occurs seven times during every 19-year period (the so-called Metonic cycle). Among the consequences of the lunisolar structure are these: (1) The number of days in a year may vary considerably, from 353 to 385 days. (2) The first day of a month can fall on any day of the week, that day varying from year to year. Consequently, the days of the week upon which an annual Jewish festival falls vary from year to year despite the festival’s fixed position in the Jewish month. The months of the Jewish calendar and their Gregorian equivalents are as follows:

The Muslim calendar (also called the Islamic calendar, or Hijrah) is a dating system used in the Muslim world that is based on a year of 12 months. Each month begins with the sighting of the crescent of the new moon as it emerges from eclipse. The months of the Muslim calendar are Muharram, Safar, Rabi I, Rabi II, Jumada I, Jumada II, Rajab, Sha’-ban, Ramadan, Shawwal, Dhu al-Qa’dah, and Dhu al-Hijjah.

In the standard Muslim calendar the months are alternately 30 and 29 days long except for the 12th month, Dhu al-Hijjah, the length of which is varied in a 30-year cycle intended to keep the calendar in step with the true phases of the Moon. In 11 years of this cycle, Dhu al-Hijjah has 30 days, and in the other 19 years it has 29. Thus the year has either 354 or 355 days. No months are intercalated, so that the named months do not remain in the same seasons but retrogress through the entire solar, or seasonal, year (of about 365.25 days) every 32.5 solar years.

There are some exceptions to this calendar in the Muslim world. Turkey uses the Gregorian calendar, while the Iranian Muslim calendar is based on a solar year. The Iranian calendar still begins from the same dating point as other Muslim calendars—that is, some 10 years prior to the death of Muhammad in ad 632. Thus, the Gregorian year ad 2009 corresponds to the Hijrah years of ah 1430-31.

Chinese Calendar

The Chinese calendar is a dating system used concurrently with the Gregorian (Western) calendar in China and Taiwan and in neighboring countries (e.g., Japan). The calendar consists of 12 months of alternately 29 and 30 days, equal to 354 or 355 days, or approximately 12 full lunar cycles. Intercalary months have been inserted to keep the calendar year in step with the solar year of about 365 days. Months have no names but are instead referred to by numbers within a year and sometimes also by a series of 12 animal names that from ancient times have been attached to years and to hours of the day.

The calendar also incorporates a meteorologic cycle that contains 24 points, each beginning one of the periods named. The establishment of this cycle required a fair amount of astronomical understanding of the Earth as a celestial body. Modern scholars acknowledge the superiority of pre-Sung Chinese astronomy (at least until about the 13th century ad) over that of other, contemporary nations.

The 24 points within the meteorologic cycle coincide with points 15° apart on the ecliptic (the plane of the Earth’s yearly journey around the Sun or, if it is thought that the Sun turns around the Earth, the apparent journey of the Sun against the stars). It takes about 15.2 days for the Sun to travel from one of these points to another (because the ecliptic is a complete circle of 360°), and the Sun needs 365% days to finish its journey in this cycle. Supposedly, each of the 12 months of the year contains two points, but, because a lunar month has only 29% days and the two points share about 30.4 days, there is always the chance that a lunar month will fail to contain both points, though the distance between any two given points is only 15°. If such an occasion occurs, the intercalation of an extra month takes place. For instance, one may find a year with two “Julys” or with two “Augusts” in the Chinese calendar. In fact, as mentioned above, the exact length of the month in the Chinese calendar is either 30 days or 29 days—a phenomenon that reflects its lunar origin.

LUNAR MONTH (CORRESPONDENCE OF LUNAR AND SOLAR MONTHS APPROXIMATE)

1—tiger

2—rabbit/hare

3—dragon

4—snake

5—horse

6—sheep/ram

7—monkey

8—chicken/rooster

9—dog

10—pig/boar

11—rat

12—cow/ox

Popcorn king Orville Redenbacher developed a hybrid popcorn with his partner, Charles Bowman. The hybrid produced plumper and more tender kernels, but no company would buy the product because it was so expensive to produce. Redenbacher went into business for himself, promoting his “gourmet” popcorn as “The World’s Most Expensive,” a marketing ploy that made Redenbacher’s product an enormous success starting in the 1970s.

Religious and Traditional Holidays

The word holiday comes from “holy day,” and it was originally a day of dedication to religious observance; in modern times a holiday may be of either religious or secular commemoration. All dates in this article are Gregorian.

Jewish holidays—The major holidays are the Pilgrim Festivals: Pesach (Passover), Shavuot (Feast of Weeks, or Pentecost), and Sukkot (Tabernacles); and the High Holidays: Rosh Hashana (New Year) and Yom Kippur (Day of Atonement).

Pesach commemorates the Exodus from Egypt and the servitude that preceded it. As such, it is the most significant of the commemorative holidays, for it celebrates the very inception of the Jewish people—i.e., the event that provided the basis for the covenant between God and Israel. The term Pesach refers originally to the paschal (Passover) lamb sacrificed on the eve of the Exodus, the blood of which marked the Jewish homes to be spared from God’s plague. Leaven (se’or) and foods containing leaven (hametz) are neither to be owned nor consumed during Pe-sach. Aside from meats, fresh fruits, and vegetables, it is customary to consume only those foods prepared under rabbinic supervision and labeled “kosher for Passover.” The unleavened bread (matzo) consists entirely of flour and water. On the eve of Pesach families partake of the Seder, an elaborate festival meal. The table is bedecked with an assortment of foods symbolizing the passage from slavery (e.g., bitter herbs) into freedom (e.g., wine). Pesach will begin at sundown on 8 April and end on 16 April in 2009. (All Jewish holidays begin at sundown.)

A distinctive Rosh Hashana observance is the sounding of the ram’s horn (shofar) at the synagogue service. Symbolic ceremonies, such as eating bread and apples dipped in honey, accompanied by prayers for a “sweet” and propitious year, are performed at the festive meals. In 2009 Rosh Hashana will begin at sundown on 18 September and will end on 20 September. Yom Kippur is a day when sins are confessed and expiated and man and God are reconciled. It is the holiest and most solemn day of the Jewish year. It is marked by fasting, penitence, and prayer. Working, eating, drinking, washing, anointing one’s body, engaging in sexual intercourse, and donning leather shoes are all forbidden. Yom Kippur begins at sundown on 27 September in 2009.

Though not as important theologically, the feast of Hanukkah has become socially significant, especially in Western cultures. Hanukkah commemorates the rededication (164 bce) of the Second Temple of Jerusalem after its desecration three years earlier. Though modern Israel tends to emphasize the military victory of the general Judas Maccabeus, the distinctive rite of lighting the menorah also recalls the Talmud story of how the small supply of nondese-crated oil—enough for one day—miraculously burned in the Temple for eight full days until new oil could be obtained. During Hanukkah, in addition to the lighting of the ceremonial candles, gifts are exchanged and children play holiday games. The festival occurs 21 through 29 Dec 2008, subsequently spanning 11 through 19 Dec 2009.

Christian holidays—The major holidays celebrated by nearly all Christians are Easter and Christmas.

Easter celebrates the Resurrection of Jesus on the third day after his Crucifixion. In the Christian liturgical year, Easter is preceded by the period of Lent, the 40 days (not counting Sundays) before Easter, which traditionally were observed as a period of penance and fasting. Lent begins on Ash Wednesday, a day devoted to penitence. Holy Week precedes Easter Sunday and includes Maundy Thursday, the commemoration of Jesus’ last supper with his disciples; Good Friday, the day of his Crucifixion; and Holy Saturday, the transition between Crucifixion and Resurrection. Easter shares with Christmas the presence of numerous customs, some of which have little to do with the Christian celebration of the resurrection but clearly derive from folk customs. In 2009 the Western churches (nearly all Christian denominations) will observe Ash Wednesday on 25 February and Easter on 12 April. For Eastern Orthodox Christians, Lent begins on 2 March and Easter will be observed on 19 Apr 2009.

Christmas commemorates the birth of Jesus Christ. Since the early part of the 20th century, Christmas has also become a secular family holiday, observed by non-Christians, devoid of Christian elements, and marked by an increasingly elaborate exchange of gifts. In this secular Christmas celebration, a mythical figure named Santa Claus plays the pivotal role. Christmas is held on 25 December in most Christian cultures but occurs on the following 7 January in some Eastern Orthodox churches.

Islamic holidays—Ramadan is the holy month of fasting for Muslims. The Islamic ordinance prescribes abstention from evil thoughts and deeds as well as from food, drink, and sexual intercourse from dawn until dusk throughout the month. The beginning and end of Ramadan are announced when one trustworthy witness testifies before the authorities that the new moon has been sighted; a cloudy sky may therefore delay or prolong the fast. The end of the fast is celebrated as the feast of “Id al-Fitr. Ramadan begins on 21 August in 2009 and “Id al-Fitr falls on 20 September of that year (all Islamic holidays begin at sundown). The Muslim New Year, Hijra, is on 17 December in 2009.

After “Id al-Fitr, the second major Islamic festival is ‘Id al-Adha. Throughout the Muslim world, all who are able sacrifice sheep, goats, camels, or cattle and then divide the flesh equally among themselves, the poor, and friends and neighbors to commemorate the ransom of Ishmael with a ram. This festival falls at the end of the hajj, the pilgrimage to the holy city of Mecca in Saudi Arabia, which every adult Muslim of either sex must make at least once in his or her lifetime. ‘Id al-Adha will be observed on 27 November in 2009.

Ashura was originally designated in ad 622 by Muhammad as a day of fasting from sunset to sunset, probably patterned on the Jewish Day of Atonement, Yom Kippur. Among the Shi’ites, Ashura is a major festival that commemorates the death of Husayn (Hussein), son of Ali and grandson of Muhammad. It is a period of expressions of grief and of pilgrimage to Karbala (the site of Husayn’s death, now in present-day Iraq). Ashura is on 6 January in 2009.

Buddhist holidays—Holidays practiced by a large number of Buddhists are uposatha days and days that commemorate events in the life of the Buddha.

The four monthly holy days of ancient Buddhism continue to be observed in the Theravada countries of Southeast Asia. These uposatha days—the new moon and full moon days of each lunar month and the eighth day following the new and full moons— have their origin, according to some scholars, in the fast days that preceded the Vedic soma sacrifices.

The three major events of the Buddha’s life—his birth, Enlightenment, and entrance into final nirvana—are commemorated in all Buddhist countries but not everywhere on the same day. In the Theravada countries the three events are all observed together on Vesak, the full moon day of the sixth lunar month, which usually occurs in May. In Japan and other Mahayana countries, the three anniversaries of the Buddha are observed on separate days (in some countries the birth date is 8 April, the Enlightenment date is 8 December, and the death date is 15 February).

Chinese holidays—The Chinese New Year is celebrated with a big family meal, and presents of cash are given to children in red envelopes. In 2009 the Chinese New Year will be on 26 January.

During the Chinese Moon Festival, on the 15th day of the 8th month of the lunar calendar, people return to their homes to visit with their family. The traditional food is moon cakes, round pastries stuffed with food such as red bean paste. The Moon Festival will occur on 2 October in 2009.

Japanese holidays—The Japanese celebrate 7-5-3 day (Shichi-go-san no hi), in which parents bring children of those ages to the Shinto shrine to pray for their continued health. This day is held on 15 November.

In mid-July (or mid-August, in some areas) the Japanese celebrate Obon (also known as Bon Mat-suri, or Urabon). The festival honors the spirits of deceased householders and of the dead generally. Memorial stones are cleaned, community dances are performed, and paper lanterns and fires are lit to welcome the dead and to bid them farewell at the end of their visit. The Shinto New Year, Gantan-sai, is celebrated on 1-3 January.

Hindu holidays—Dussehra celebrates the victory of Rama over Ravana, the symbol of evil on earth. In 2009 Dussehra falls on 28 September. Diwali is a festival of lights devoted to Laksmi, the goddess of wealth. During the festival, small earthenware lamps filled with oil are lighted and placed in rows along the parapets of temples and houses and set adrift on rivers and streams. Diwali is on 17 October in 2009. Sivaratri, the most important sectarian festival of the year for devotees of the Hindu god Shiva, occurs on 23 February in 2009. Holi is a spring festival, probably of ancient origin. Participants throw colored waters and powders on one another, and, on this day, the usual restrictions of caste, sex, status, and age are disregarded. It will be on 11 March in 2009.

Sikh holidays—Sikhs observe all festivals celebrated by the Hindus of northern India. In addition, they celebrate the birthdays of the first and the last Gurus and the martyrdom of the fifth (Arjun) and the ninth (Tegh Bahadur). In 2009 Guru Nanak Dev Sahib’s birthday is celebrated on 2 November, and that of Guru Gobind Singh Sahib is celebrated on 5 January. On 16 June Arjun’s martyrdom is observed. Kachi lassi (sweetened milk) is offered to passersby to commemorate his death. On 24 November the martyrdom of Tegh Bahadur is observed.

Baha’i holidays—The Baha’i New Year (Naw Ruz) in 2009 will fall on 21 March (all Baha’i holidays begin at sundown). Other important observances include the declaration of the Bab on 22 May, the Baha ‘Ullah’s birth (11 November), and Ascension (28 May).

Zoroastrian holidays—Noruz (New Day) is on 21 March for 2009, and the 26th of that month is Khor-dad Sal, the birth of the prophet Zarathustra.

African American holiday—Kwanzaa (Swahili for “First Fruits”) is celebrated each year from 26 December to 1 January and is patterned after various African harvest festivals. Maulana Karenga, a black-studies professor, created Kwanzaa in 1966 as a nonreligious celebration of family and social values. Each day of Kwanzaa is dedicated to one of seven principles: unity (umoja), self-determination (kuji-chagulia), collective responsibility (ujima), cooperative economics (ujamaa), purpose (nia), creativity (kuumba), and faith (imani).

The perpetual calendar is a type of dating system that makes it possible to find the correct day of the week for any date over a wide range of years. Aspects of the perpetual calendar can be found in the Jewish religious and the Julian calendars, and some form of it has appeared in many proposed calendar reforms.

To find the day of the week for any Gregorian or Julian date in the perpetual calendar provided in this table, first find the proper dominical letter (one of the letters A through G) for the year in the upper table. Leap years have two dominical letters, the first applicable to dates in January and February, the second to dates in the remaining months. Then find the same dominical letter in the lower table, in whichever column it appears opposite the month in question. The days then fall as given in the lowest section of the column.

Civil Holidays