'Spring forward, fall back" - it's time to change our clocks again this Sunday. Time seems so simple: Add an hour here, subtract it there. It all evens out over the course of a year. But is time really that easy? See how much you know about the history of time.
True or False?
1. A day is exactly 24 hours long.
2. The United States extends across four time zones.
3. Standard time in the US was set in 1883 chiefly because of railroad proliferation.
4. The word "month" comes from "monk." Monastic monks were the first to develop calendars using days, weeks, and months.
5. New Year's Day on the Egyptian sun calendar (our July 19) corresponded with the start of the annual flooding of the Nile.
6. At the vernal and autumnal equinoxes, the sun crosses the equator, and day and night are of equal length. And so, on these two days, the sun rises in the north and sets in the south.
7. The Julian calendar was introduced by Julius Caesar in an effort to reform the confusing Roman calendar. To make the change, the calendar in that first year, 46 BC, had 445 days. Forever after, that year was known as "The Year of Confusion."
8. The calendar we use today is known as the Gregorian calendar.
9. Greenwich Mean Time and Universal Time are two different time standards.
10. The year 2000 will be the first year of the third millennium.
1. False. The mean solar day is 24 hours, 3 minutes, and 56.55 seconds long.
2. False. There are eight time zones in the US, from the Virgin Islands in the east (Atlantic Time) to Alaska's Aleutian Islands in the west (Bering Time zone).
3. True. In America of the 1870s, individual railroads developed their own time systems. At one point there were 50 time systems in use across the country.
4. False. Month is from "moon." The time it takes the moon to complete its cycle, approximately 29.5 days, is one "moonth."
5. True. The ancient Egyptians set up their calendar with three seasons of four 30-day months each. The seasons were "inundation," "sowing," and "harvesting." The 12 months added up to only 360 days. Eventually, five feast days were tacked on to the end of the year.
6. False. The sun rises precisely in the east and sets precisely in the west on those days. Ancient peoples used the equinoxes to determine the precise directions of east and west.
7. True. Starting in 45 BC, the Julian calendar had 365 days, and 366 every fourth year.
8. True. Pope Gregory XIII reformed the Julian calendar in 1582.
9. False. They are two names for the same worldwide time standard. Greenwich, a suburb of London, is on the prime meridian.
10. False. It is the last year of the second millennium. The third millennium starts with the year 2001.