Articles

Short pieces on the things the countdown depends on. Each one ends with its sources.

• How many days are left in the year? — The live number, a table for every month, and how the count is worked out.
• Why leap years exist, and why February gets the extra day — 365.2422 days, Julius Caesar, Pope Gregory XIII, and the odd-numbered months of Rome.
• Where New Year arrives first, and where it arrives last — Kiritimati at UTC+14, Baker Island at UTC−12, and the 26 hours in between.
• How time zones work — Longitude, 15° an hour, UTC offsets, and why the zone map is bent.
• Why time zones exist — Railways, Sandford Fleming and what the 1884 conference actually decided.
• How many seconds, hours and weeks are in a year? — 31,536,000 seconds, 8,760 hours, 52 weeks and a day — the table, common and leap.
• When the year ends around the world — Midnight on 1 January for major cities, expressed in UTC — a 26-hour wave.
• Midnight sun and polar night — Why the Sun stays up for months near the poles, and why the calendar keeps counting.
• Solstices and equinoxes — Why days lengthen and shorten, the longest and shortest days, and why neither is New Year.
• Solar and lunar eclipses — What lines up, how often, how long, and why the Moon turns red.
• UTC, GMT and leap seconds — What clocks are set to, atomic time, GMT vs UTC, and the 27 leap seconds.
• Daylight saving time — What it is, who uses it, and why the hours digit can be one more than you expect.
• Half-hour and quarter-hour time zones — India, Nepal, Newfoundland and every other zone that is not a whole hour from UTC.
• Why New Year is on 1 January — Janus, Roman consuls, a medieval free-for-all, and two reforms that kept the date.