2012年9月21，22北美机经

Brief History of Calendar

①  Calendar, system of measuring time for the needs of civil life, by dividing time into days, weeks, months, and years. Calendar divisions are based on the movements of the earth and the regular appearances of the sun and the moon. A day is the average time required for one rotation of the earth on its axis. The measurement of a year is based on one revolution of the earth around the sun and is called a seasonal, tropical, or solar year. A solar year contains 365 days, 5 hr, 48 min, and 45.5 sec. A month was originally calculated by ancient peoples as the time between two full moons (29.5 days). This measurement, called a synodic, or lunar month, resulted in a lunar year of 354 days, 11days shorter than a solar year. In modern calendars, however, the number of days in a month is not based on the phases of the moon. The length of the months is approximately one-twelfth of a year (28 to 31 days) and is adjusted to fit the 12 months into a solar year. The week was derived from the Judeo-Christian tradition requiring rest from labor every seventh day. It is not based on a natural phenomenon.

【重点词汇】

1)    Division: the ~ of a large unit into two or more distinct parts is the act of separating into these parts. 分割，分裂；

2)    Rotation：a circular movement, 旋转

3)    Synodic：relating to or involving a conjunction or two successive conjunctions of the same star, planet, or satellite, 天体会合

4)    Lunar：relating to the moon, 阴历的

5)    Be derived from：源自于

6)    Judeo-Christian：being historically related to both Judaism and Christianity，同是犹太教与基督教的

【段落主题】

Calendar divisions are based on the movements of the earth and the regular appearances of the sun and the moon：a day, a month, (lunar month), a solar year.

①  The Egyptians created a calendar at a very early stage, based on their observations of the movements of the Sun and the stars. Perhaps representing one of the first attempts at making a calendar are the remnants of stone circles from around 8000 BC in the southwestern corner of modern Egypt. These stone circles may have been used to map the movement of the heavenly bodies. The Egyptians probably created a calendar because it was so important for their survival to know when the Nile’s flood would come. They divided each day into 24 hours, 12 for the daytime and 12 for the night. A period of ten days made up a week, and one month included three such weeks, or 30 days. A year comprised 12 months and was divided into three seasons of four months each. To the 360 days of the 12 months in a year, the Egyptians added 5 more days, which they referred to as the birthdays of several gods. Thus, an Egyptian year totaled 365 days, remarkably close to the 365¼ days it takes the Earth to go around the Sun. There was no concept of leap year, so the calendar fell behind by one day every four years.

【重点词汇】

1)     Remnant: a small part or portion that remains after the main part no longer exists, 残余部分，残迹

2)     Heavenly body：a planet, star, moon, or other natural object in space, 天体

3)     Leap year：闰年

【段落主题】

The Egyptians created a calendar, based on their observations of the movements of the Sun and the stars, because it was so important for their survival to know when the Nile’s flood would come.

②  In 45 BC, Julius Caesar decided to use a purely solar calendar upon the advice of the Greek astronomer Sosigenes. This calendar, known as the Julian calendar, fixed the normal year at 365 days, and the leap year, every fourth year, at 366 days. In this way the extra 1/4 day a year could be accounted for. The Julian year, however, was 11 min and 14 sec longer than the solar year (a solar year contains 365 days, 5 hr, 48 min, and 45.5 sec, while 1/4 day equals to 6hr). This discrepancy accumulated until by 1582 when the vernal equinox occurred 10 days early and church holidays did not occur in the appropriate seasons. To make the vernal equinox occur on March 21, as it had in AD 325, the year of the First Council of Nicaea, Pope Gregory XIII issued a decree dropping 10 days from the calendar. To prevent further displacement, he instituted a calendar, known as the Gregorian calendar, which provided that century years divisible evenly by 400 should be leap years and that all other century years should be common years. Thus, 1600 was a leap year, but 1700 and 1800 were common years.

【重点词汇】

1)     Solar calendar: 【天文学】太阳历(Gregorian calendar)

2)     Astronomer: 天文学家

3)     Julian calendar：罗马儒略历

4)     Be account for：explain sth or give the necessary information about sth. 解释

5)     Discrepancy：a difference between conflicting facts or claims or opinions, 差异

6)     Vernal equinox：春分；春分点（约在3月20日）

7)     Decree：an official order or decision, especially one made by the rule of a country, 法令

8)     Displacement: the removal of something from its usual place or position by something which then occupies that place or position, 替代

9)     Divisible evenly：均分

【段落主题】

In 45 BC, Julius Caesar—Julian Calendar;

In AD 325, Pope Gregory XIII-- Gregorian calendar