Leap Year 2016: Why does February have 29 days every four years?

shappy1978

浏览: 698569 次
性别:
来自: 广州

最近访客更多访客>>

u012363178

lingzhixue

hsjiang79

bobby318

博主相关

博客

微博

相册

留言

关于我

文章分类

社区版块

存档分类

博客分类：

生活

1 2 3 4 5 6 7 8 9 10 11 12
31 30 31 30 31 30 31 29 31 30 31 30
31 28 31 30 31 30 31 31 30 31 30 31

https://zh.wikipedia.org/wiki/%E5%B0%A4%E5%88%A9%E7%83%8F%E6%96%AF%C2%B7%E5%87%B1%E6%92%92

http://www.thefullwiki.org/Julian_calendar

http://baike.baidu.com/view/169027.htm

//Julian: boy's name, Julia and Romeo

https://zh.wikipedia.org/wiki/%E5%84%92%E7%95%A5%E6%9B%86

February 29 crops up every four years, but what is a leap year?

Frogs are associated with leap years. This is a leaping frog Photo: Getty

Why do we have leap years?

A leap year, where an extra day is added to the end of February every four years, is down to the solar system's disparity with the Gregorian calendar.

A complete orbit of the earth around the sun takes exactly 365.2422 days to complete, but the Gregorian calendar uses 365 days.

So leap seconds - and leap years - are added as means of keeping our clocks (and calendars) in sync with the Earth and its seasons.

Why does the extra day fall in February?

All the other months in the Julian calendar have 30 or 31 days, but February lost out to the ego of Roman Emperor Caesar Augustus.

Under his predecessor Julius Caesar, February had 30 days and the month named after him - July - had 31. August had only 29 days.

When Caesar Augustus became Emperor he added two days to 'his' month to make August the same as July.

So February lost out to August in the battle of the extra days.

Why does the woman propose on a leap year?

Leap years are also marked as a time for women to propose to men.

One theory is that the custom dates back to the 5th Century, when, legend has it, an Irish nun called St Bridget complained to St Patrick that women had to wait too long for their suitors to propose. St Patrick then supposedly gave women the chance to ask the question every four years.

The tradition is not thought to have become commonplace until the 19th Century.

Then there's the theory that Queen Margaret of Scotland was behind the fabled Scottish law of 1288. The law allowed unmarried women the freedom to propose during a leap year, and the man who refused was handed a fine.

The truth behind this tale is dubious at best - after all Queen Margaret was just eight years old when she died and scholars have been unable to find a record of the law.

Street smart: Sandra Bullock proposes to Ryan Reynolds in 'The Proposal' - Pop the question now, ladies, before he humiliates you with his proposal Sandra Bullock proposes to Ryan Reynolds in 'The Proposal' Photo: REX

Others argue that the tradition of women proposing on this day goes back to the times when the leap year day was not recognised by English law. Under this theory, if the day had no legal status, it was acceptable to break with the convention of a man proposing.

Women either have to wear breeches or a scarlet petticoat to pop the question, according to tradition.

In Denmark, if a man turns down a proposal they must give the woman 12 pairs of gloves and in Finland the penalty is fabric for a skirt.

According to research conducted by Beefeater, 20 per cent of women said they would like to propose to their partner. Despite the fact that almost a third of women said they would be worried about their partner's reaction. However, more than half of men (59 per cent) would love their girlfriends to get down on one knee.

To that end, the chain has created a 'Leap Year Proposal Package' should you wish to pop the question at one of its establishments.

Research from The Stag Company yielded similar results, with more than half of men saying they would accept a propsal from their girlfriend, and the majority asserting that they would like to be given a ring by their partner.

Yet just 15 per cent of women said they would consider proposing.

Although there's a theory that most unmarried men would love for their female partners to propose, recent research suggests Leap Year-inspired betrothals are doomed to failure.

Technically, a leap year isn't every four years

The year 2000 was a leap year, but the years 1700, 1800 and 1900 were not.

There's a leap year every year that is divisible by four, except for years that are both divisible by 100 and not divisible by 400.

The added rule about centuries (versus just every four years) was an additional fix to make up for the fact that an extra day every four years is too much of a correction.

Julius Caesar vs Pope Gregory

Pope Gregory XIII (1502-1585)

The Roman calendar did have 355 days with an extra 22-day month every two years, until Julius Caesar became emperor and ordered his astronomer Sosigenes to devise a better system in the 1st Century.

Sosigenes decided on a 365-day year with an extra day every four years to incorportate the extra hours, and so February 29th was born.

As an earth year is not exactly 365.25 days long Pope Gregory XIII's astronomers decided to lose three days every 400 years when they introduced the Gregorian calendar in 1582.

The maths has worked ever since but the system will need to be rethought in about 10,000 years' time.

Is February 29 a bank holiday?

It's not - but there is a campaign to make February 29 a bank holiday.

Workers have realised that every leap year, they have to work one extra day for no extra pay.

If a person earns the national average salary of £26,500 a year, that works out at £2,208.33 per monthly payslip – which breaks down to £71.24 per day in a 31-day month but a daily wage of £78.87 in February.

This realisation prompted Karl Savage, who was a high school teacher from Maryland, to try and kick-start the “No Work on Leap Day Revolution” in 2008, when the extra day fell on a Friday.

What is a leap second?

Leap years are not directly connected to leap seconds, but both are for the purpose of keeping the earth's rotations in line with our clocks and calendars.

Leap seconds are added to bring the earth's rotation into line with atomic time. A leap second was added at the end of June last year, when immediately before midnight dials read 11:59:60.

Atomic time is constant, but the Earth’s rotation is gradually slowing down by around two thousandths of a second per day.

A view of the Earth and the Moon Leap seconds are crucial to ensuring the time we use does not drift away from time based on the Earth's spin Photo: ALAMY

Leap seconds are therefore crucial to ensuring the time we use does not drift away from time based on the Earth's spin. If left unchecked, this would eventually result in clocks showing the middle of the day occurring at night.

The extra second can sometimes cause problems for some networks which rely on exact timings. When a last leap second was added in 2012 Mozilla, Reddit, Foursquare, Yelp, LinkedIn, and StumbleUpon all reported crashes and there were problems with the Linux operating system and programmes written in Java.

Other calendars require leap years

The modern Iranian calendar is a solar calendar with eight leap days inserted into a 33-year cycle.

The Indian National Calendar and the Revised Bangla Calendar of Bangladesh arrange their leap years so that the leap day is always close to February 29 in the Gregorian calendar.

What if you're born on February 29?

The chances of having a leap birthday are one in 1,461. People who are born on February 29 are referred to as "leaplings", or "leapers". In non-leap years, many leaplings choose to celebrate their birthday on either February 28 or March 1, while purists stick to February 29 for the occasion.

Some suggest those born before midday on February 29 should celebrate their birthdays on February 28, while those born in the afternoon and evening of the 28th should celebrate their special day on March 1 (St David's Day).

Those born around midday are less fortunate when it comes to picking a side.

About 4.1 million people around the world have been born on the 29th.

Pisces is the zodiac sign of a person born on February 29, and amethyst is the birthstone for this month.

Are you celebrating a birthday on February 29th? Majestic Wine is offering a free bottle of champagne (to those who buy six bottles).

(We gather the offer is open to those over 18 and not just 72-year-olds as you might imagine...)

Born on the 29th February? Buy six bottles of wine from us this weekend and we'll give you a bottle of Veuve on us!pic.twitter.com/KVQD4vU4ZL
— Majestic Wine (@majesticwine) February 25, 2016

Famous people born on a leap day

The chances of having a birthday on a leap day are extremely slim - the odds are one in 1,461 to be exact - and there's quite an eclectic mix of famous people born on the day.

Sir Dave Brailsford has transformed Britain's cycling fortunes Photo: GETTY IMAGES

John Byrom - Romantic poet
Pope Paul III - 16th Century pontiff
George Bridgetower - 19th Century musician
Ann Lee - leader of the Shakers
Gioacchino Rossini - Italian composer
Charles Pritchard - British astronomer
Sir Dave Brailsford - English cyclist and coach
Tony Robbins - Motivational speaker
Alan Richardson - composer
Darren Ambrose - English footballer
Ja Rule - rapper

Damn I thought I was the most famous leap year baby but pope Paul the third might have me beat lol...
— Ja Rule (@Ruleyork) February 24, 2016

Posted by Honor Society of Leap Year Day Babies on Friday, 29 January 2016

On this day in...

What other major events have happened on February 29th?

In 1996, the siege of Sarajevo was lifted after almost four years.
In 1984, Pierre Trudeau resigned as Prime Minister of Canada.
In 1964, the Queen's cousin, Princess Alexandra, gave birth to a son, James Ogilvy.
In 1960, thousands died as an earthquake devastated Agadir, Morocco.
In 1940, Hattie McDaniel became the first black person to win an Oscarfor her role in Gone with the Wind.

The leap year on stage and screen

The plot of Gilbert & Sullivan's Pirates of Penzance revolves around a character, Frederic, who was born on February 29.

Frederic is due to be released from his apprenticeship with a band of pirates on his 21st birthday.

However, he realises that because he only has a birthday once every four years, he must remain an apprentice and serve another 63 years before he can join Mabel, his one true love. She agrees to wait for him faithfully until that day.

The 2010 romantic comedy Leap Year, starring Amy Adams, Matthew Goode and Adam Scott, tells the story of an uptight decorator who travels from the United States to Ireland to propose to her boyfriend.

However she faces a major setback when bad weather threatens to derail her plans.

The film was described by The Telegraph's Tim Robey as "abysmal".

Even Matthew Goode, one of the films stars, said: "It’s turgid. I just know that there are a lot of people who will say it is the worst film of 2010."

Leap year recipes

There are no specific recipes for leap years, but how about cooking up somefrogs' legs?

Although not popular in Britain, the French eat about 4,000 tons of frogs’ legs a year, equivalent to 60-80 million frogs.

Since edible frogs are now a protected species in France, frogs’ legs are imported from Indonesia.

Alternatively, these four recipes have a link to frogs, the number four and leap year traditions.

The leap year capital of the world

The city of Anthony which straddles Texas and New Mexico in the US, is the self-proclaimed Leap Year Capital of the World.

A four-day leap year festival is held there each leap year that includes a huge birthday party for all leap year babies.

Festivities begin on February 25 and continue until February 29, when there is a parade followed by a birthday dinner.

Posted by Leap Year Capital of the World on Friday, 5 February 2016

Are you ready to celebrate in Anthony, Tx?
Posted by Leap Year Capital of the World on Tuesday, 23 February 2016

Leap year proverbs

A flock of sheep Will 2016 prove a bad year for sheep? Photo: Alamy

In Scotland, a leap year is thought to be bad for livestock. This is why the Scottish sometimes say, "Leap year was ne’er a good sheep year."

In Italy, where they say "anno bisesto, anno funesto" (which means leap year, doom year), there are warnings against planning special activities such as weddings. The reason?

"Anno bisesto tutte le donne senza sesto" which means "In a leap year, women are erratic."

Facts about leap years

A view over Rio de Janeiro Preparations for the Rio Olympics are well underway Photo: AFP

The Summer Olympic Games are always held in a leap year. This year, they take place in Rio de Janeiro, Brazil.
US presidential elections are held every four years, in a leap year.
In Greece couples often avoid getting married in a leap year, believing it to be bad luck
Food for thought: If you work on a fixed annual wage, today is just one more day's work than you would usually have to do for your salary.
As touched on above, a year that is divisible by 100, but not by 400, is not technically a leap year. Therefore 2000 was a leap year under the Gregorian calendar, as was 1600. But 1700, 1800 and 1900 were not. "There's a good reason behind it," Ian Stewart, emeritus professor of mathematics, told the BBC. "The year is 365 days and a quarter long - but not exactly. If it was exactly, then you could say it was every four years." Pope Gregory and his astronomers' solution will have to be rethought in around 10,000 years, Prof Stewart points out.
February 29 also marks Rare Disease Day.
Leap years are also known as intercalary or bissextile years.

Google have done a doodle!

分享到：

Win10 Resource | 红月亮

2016-02-29 19:56
浏览 1059
评论(0)
分类:非技术
查看更多

发表评论

您还没有登录,请您登录后再发表评论

最近访客更多访客>>

博主相关

文章分类

社区版块

存档分类

最新评论