45 Fun Facts About International Date Line

The International Date Line runs mostly through which ocean?

Pacific: the line runs from pole to pole but mostly crosses the Pacific, which Magellan reportedly named 'peaceful' for the calm water he found after stormy seas.

Which line of longitude does the International Date Line roughly follow?

180°, though the line zigzags east and west of that meridian so that island groups and territories each keep a single calendar date.

What happens to the calendar date when you cross the date line travelling eastbound?

It goes back one day: an eastbound traveller turns the calendar back at the line and so lives through part of that date a second time.

Legally, what kind of line is the International Date Line?

A cartographic convention: no treaty or international body fixes the line, so the countries it passes near are free to choose which date they keep.

Travelling westward around the world, how must you set your clock for every 15° of longitude crossed?

Back one hour: solar noon shifts four minutes for every degree of longitude, so a place 15° farther west reaches noon an hour later.

The date line's first bend away from the meridian passes east of Wrangel Island and which Russian peninsula?

The line jogs east around the Chukchi Peninsula and Wrangel Island, keeping Chukotka and all of Russia on the Asian side of the date line.

Which unofficial US Navy title do sailors earn by crossing the date line?

Golden Dragon honors mark crossing the date line, and some sailors wear a golden dragon tattoo to show it; Shellbacks have crossed the equator.

Because of the date line, Big Diomede and Little Diomede are nicknamed what?

Tomorrow Island and Yesterday Island: Russia's Big Diomede lies a day ahead, and after the Soviets built a base there its villagers were moved to the mainland, splitting families.

What has often joined Alaska's Little Diomede to Russia's Big Diomede across the date line?

A bridge of sea ice has usually formed between them in winter, and Little Diomede's villagers long ploughed a runway on the frozen sea for supply flights, until the ice grew too thin.

Which US island chain does the date line bend west to keep on the American date?

The Aleutian Islands arc west from the Alaska Peninsula to Attu, which Japanese troops seized in June 1942 before US forces won it back in May 1943.

Which two US islands, one of them Amelia Earhart's destination, are the last places to end each day?

Howland and Baker see each day out last; a runway was cleared on Howland for Earhart's 1937 refuelling stop, but she vanished on the way and never touched down.

Around which country does the date line swing far to the east, almost reaching 150°W?

Kiribati's president, Teburoro Tito, simply announced the change, and from 1 January 1995 the line has run along the country's many-cornered eastern boundary.

Which European country abstained from the 1884 International Meridian Conference's vote choosing the world's prime meridian?

France abstained after arguing that the prime meridian should be neutral, cutting through no great continent, neither Europe nor America.

Which observatory's meridian did the 1884 International Meridian Conference adopt as longitude 0°?

Greenwich was chosen because nearly two-thirds of the world's ships already used charts based on its meridian, so it caused the least disruption.

Which two major cities are the first to reach each new calendar day?

Auckland and Wellington keep New Zealand time, so Auckland's Sky Tower fireworks greet the New Year only about an hour after the first small island nations do.

What new name was uninhabited Caroline Island given in 1997?

Millennium Island welcomed 2000 with chanting and dance by singers and dancers who travelled out to the normally empty atoll for the occasion.

Why do three calendar dates briefly coexist on Earth each day?

Zones span 26 hours rather than 24, so each day the newest date has already begun at one end of the map before the oldest has run out at the other.

When Russia handed Alaska to the United States in 1867, which calendar did Alaska stop using?

The Julian calendar ran 12 days behind the Gregorian one, and Alaska also moved to the American side of the date line, so the 18 October handover was still early October by Russian dates.

Where did Magellan's surviving crew, sailing home in 1522, first learn from Portuguese islanders that their log was a day behind?

Cape Verde: the crew had logged every day without a gap, yet islanders said Thursday when the ship said Wednesday; Gasparo Contarini explained that sailing west had cost a day.

Which Asian country sat on the American side of the date line until the end of 1844?

The Philippines traded with Spanish Mexico, so it kept the American date until its trade turned toward China and the Dutch East Indies.

When F-22 Raptors lost navigation at the date line in 2007, how did they get back to Hawaii?

Following their tanker planes, the jets made it back to Hickam, and once the software was fixed they flew on to Kadena for their first overseas deployment.

When Samoa switched to the American date in 1892, which day did it live through twice?

Samoa repeated 4 July, US Independence Day, in 1892, living Monday 4 July twice after American traders persuaded King Malietoa Laupepa to adopt the American date.

What is a hurricane called once it crosses west of the date line, north of the equator?

A typhoon: Hurricane John crossed the date line in late August 1994 and became Typhoon John, then crossed back on 8 September and was a hurricane once more.

Why did Samoa move across the date line in 2011?

To ease trade with Australia and NZ: the jump put Samoa three hours ahead of Sydney instead of 21 hours behind it.

Which neighbour crossed the date line along with Samoa at the end of 2011?

Tokelau's main transport and communications links run through Samoa, so the three atolls followed it across the line, while American Samoa stayed on the American side.

Which atoll with a US Army missile range skipped Saturday 21 August 1993 to share the Marshall Islands' date?

Kwajalein moved its workweek to Tuesday through Saturday, so its working days still lined up with Monday to Friday in the United States.

Why did a republic push the date line around its eastern islands?

The country straddled it, leaving four shared weekdays, so its eastern islands skipped Saturday 31 December 1994 and the line in effect moved east around the whole country.

As Japan attacked Pearl Harbor in 1941, what was the date in Tokyo?

8 December, because Tokyo lies across the date line from Hawaii, where it was still the 7th; Japan's landing in Malaya began before the raid yet carries the later date too.

Which two places sit east of the date line, a whole day behind nearby Samoa?

The Cook Islands and Niue keep the American date, and the Cook Islands got there in 1899 by law: Christmas Day was stretched over two days, so islanders celebrated it twice.

The meridian the date line mostly follows crosses land in which island nation?

Fiji: the meridian cuts right across its island of Taveuni, but the date line bends around the country, so all of Fiji keeps a single date.

Which author wrote that crossing the date line in 1895 put his family on Sunday and himself on Tuesday?

Mark Twain was on a worldwide lecture tour to pay off debts after his publishing company failed, and wrote up the crossing in Following the Equator.

Why does one Jewish date line bend around Asia's coast rather than follow a meridian?

A street would split Sabbath, so the line bends, which puts Japan on America's side; one travellers' guide tells visitors to keep the local Sabbath in full and avoid forbidden work the next day too.

The 1884 International Meridian Conference agreed the Universal Day but explicitly declined to do what?

The conference agreed a Universal Day beginning at mean midnight on the prime meridian but declared that it would not propose or agree any time zones, leaving those to individual governments.

On which local day do Seventh-day Adventists in Tonga, in the Western Hemisphere, keep the Sabbath?

Sunday: the church counts days as if the date line followed the meridian Tonga lies just east of, so Tongan Sunday matches Saturday across the line.

Which American author's 1841 tale 'Three Sundays in a Week' turns on two captains' clashing calendars?

Edgar Allan Poe has a stubborn great-uncle swear the narrator may marry only when three Sundays fall in one week, and the captains, home from opposite trips round the world, hold him to his word.

In Around the World in Eighty Days, who discovers that Phileas Fogg has come home a day earlier than he thinks?

Passepartout went to book Fogg's wedding to Aouda and learned it was still Saturday, so Fogg reached the Reform Club in time to win his bet.

Which Italian novelist wrote The Island of the Day Before, a tale of a castaway and the date line?

Umberto Eco strands his hero on a deserted ship anchored off an island that, he convinces himself, lies across the date line in the day before, and since he cannot swim it stays out of reach.

Bret Harte's 1867 poem 'The Lost Galleon' concerns a Spanish ship sailing between Acapulco and which port?

Manila: sailing there from Acapulco, the galleon San Gregorio loses its patron saint's day at the date line and is doomed to drift near it for centuries trying to win it back.

On which date did a flight land in Hawaii after leaving New Zealand just after midnight on New Year's Day 2018?

31 December 2017: a ten-minute delay pushed take-off from 11:55 p.m. past midnight, so the passengers left in 2018 and landed in 2017 with New Year's Eve still to come.

The date line passes just east of the Russian island where which explorer died after being shipwrecked in 1741?

Vitus Bering died on the island now named after him; about half his crew survived the winter, and their news of rich furs drew Russian traders east.

Which three US insular areas lie west of the date line?

Guam, Northern Marianas and Wake Island lie west of the line and keep the Asian date, hence Guam's motto 'Where America's Day Begins'.

A deadline set for the end of a day 'AoE', Anywhere on Earth, passes at what time in UTC?

Noon the next day: the date survives until its last midnight, which falls in UTC-12, so an AoE deadline holds until every place on Earth has finished that day.

Which 1964 event did Syncom 3, a satellite parked above the equator at the date line, relay to American TV?

The Summer Olympics reached America live from Tokyo, yet NBC showed only the opening ceremony that way, and delayed even that on the West Coast rather than interrupt its late-night schedule.

Which Victorian author set readers a puzzle on where each day changes its name?

Lewis Carroll posed it in A Tangled Tale, his magazine puzzle series, then postponed the answer because he was 'so entirely puzzled by it'; the answer is the date line.

Which kind of US Navy vessel lay across the date line at midnight as the year 2000 began?

A submarine, the USS Topeka, hovered underwater with its bow in one year and its stern in the other, so its crew could stroll between 1999 and 2000.