Christian Conference Season

One thing I quite enjoy going to is Christian conferences. Depending onn emphasis, there is the chance to network with other people who love God, to have fellowship and to have teaching.

In the second quarter of 2013 there are three I have decided to go to.

First up is on 18 May and is the London Men's Convention. I have been to quite a few of these and the teaching is sound, Bible-based and relevant. And they also recognise the range of Christisn masculinity (no expecting men to conform to one stereotype).

The speakers for the early convention are Graham Beynon, Jonty Allcock and John Tindall.

The second is the following Saturday and is Unbelievable?, which looks at apologetics, and features the Amy Orr-Ewing, the Alister McGrath and a Peter Williams among its speakers.

I am looking forward to this as I think apologetics - being able to contend for the faith that was delivered nearly two millennia ago (Jude 3) and to always have a defence for the hope we have (I Pet 3:15).

These are two I have already booked to go on. The third is one I intend to book for and is the Bristol Men's Convention on 8 June, which is something I've not been to before.

If These Churches Feel So Strongly About Poverty..

Here we go again. One might imagine that with it being Easter churches might put out statements which are - at least - vaguely connected to Jesus.

Four left-wing pressure groups denominations - the Church of Scotland, the Methodist Church of Great Britain, the United Reformed Church and the Baptist Union of Great Britain - have decided to condemn welfare cuts, whilst Work & Pensions Secretary Iain Duncan-Smith has said that the United Kingdom is not managing to cut the welfare bill.

I remember as an undergraduate there would often be motions at JCR meetings mandating the Committee to go on marches to represent the JCR. I once heard this concept mocked - quite rigthly - as feeling so strongly about some issue that you're going to stay back in Oxford and mandate other people to march on your behalf.

And this is how these denominations are coming across.

One source of revenue for the churches is from the Government. Er, actually the money the Government has coming in from taxpayers of all religions and none. And this is Gift Aid, which is - on one level - a marvellous idea as it increases charities' revenues.

But, if the churches didn't take their Gift Aid, then there would be more money for the Government to spend on welfare. Simples! So why don't these churches call for this? Or at the very least treat the Gift Aid money as money from the Government taxpayers to be spent exclusively on projects to help the poor people they talk about?

Put your money where your mouth is

One event in the early church was the prophesied famine covered in Acts 11:27-30, and Paul tells the Roman church about churches elsewhere which were pleased to help the poor in the Jerusalem church (Rom. 15:25-29)

How pleased the church in Jerusalem must have been when Paul arrived bearing photos of protest marches and examples of postcards that the young churches had sent to Caesar asking him to "do something" to help.

No! The early church dug into their pockets and gave sacrificially to help the poor. What I find in the Bible is that it's up to the people of God, and not the State, to do this.

What did the Victorian Christians do when they saw a practical need? They got off their backsides and did something. And that attitude is still there today, with Christian-based charities helping the poor and suffering, and individual Christians working for secular charities.

Yet from the hierarchy of these denominations it seems that all you need to do is make a little political point attacking the Government and you have done your job. No need to get one's hands dirty. No need to reach into one's pocket. Just moralise about the Government's duty to reach into other people's pockets.

It's Finger Lickin' Bad

One thing that really gets on my nerves - and I saw an example while getting some odds and ends this evening after Doctor Who - is the poor quality of food hygiene in supermarkets.

Back in the mid-nineties I worked in various food factories in Leicester and one thing was essential - the holding of the Chartered Institute of Environmental Health's Basic Food Hygiene Certificate.

Although I am not the world's tidiest person, when it comes to food hygiene I am fussy. Open a packet of cereal and its contents go in an airtight container. Never use the same knife for meat and then something else, or even for two different types of meat. Separate chopping boards (although not the colour-coded ones).

But it seems that basic food hygiene is an alien concept in modern supermarkets.

The most common is when they get carrier bags for you. Finger in gob, lick and get the carrier bag and then touch your food.

A few weeks back there was a daily ritual at the supermarket over the road from where I work. I would do some food shopping, and whoever was at the till would - you guessed it - put finger in gob etc.. The next stage of the ritual was my finding the duty manager and explaining why it is unhygenic. I get the promise that all till staff will be told and it will not happen again. And then the next day - yep, you've guessed that as well. So, by now I know that all duty managers are thinking of is "what shall I say to make annoyed customer shut up and clear off?".

Or else there is the chewing gum fad. One thing we learned was that you never chew gum (or anything else) or eat while handling food. But now it's chew chew chew. I remember shopping and seeing the actions of one woman at the fruit and veg. Chew, chew. Hand in gob. Sort chewing gum out. Pick up fruit and carry on sorting. I did explain to the duty manager why that is unhygenic, but couldn't get her to comprehend.

Or else the sneezers. I recently shopped, put my shopping on the belt at the till, and the till operator sneezed into her hands. And then carried dealing with the shopping of the person in front of me. So I just started putting my shopping back in the basket and went to another till.

General Elections Without Scotland

With the Scottish Government having announced that the independence referendum would be on 18 September 2014, there is one - of the many consequences - of independence, which would be that MPs from Scottish constituencies would no longer have any reason to sit in the House of Commons.

And with this in mind, time to have a look at what election results would be without Scotland. This assumes that the political history in England, Wales and Northern Ireland runs the same as in the real history.

We begin with July 1945:

Labour - 356

Conservative - 163*

Liberal - 12

Ulster Unionist - 9

National Liberal - 8

Independent - 7

Irish Nationalist - 2

Independent Labour - 2

Independent National - 2

Communist - 1

Common Wealth - 1

National - 1

Independent Progressive - 1

Independent Ulster Unionist - 1

[* Includes the sitting Speaker, Douglas Clifton-Brown, MP for Hexham]

Labour majority 145

February 1950:

Labour - 278

Conservative - 246*

National Liberal - 11

Ulster Unionist - 10

Liberal - 7

Irish Nationalist - 2

[* Includes the sitting Speaker, Clifton-Brown, MP for Hexham]

Labour majority 3

October 1951:

Conservative - 264*

Labour - 260

National Liberal - 13

Ulster Unionst - 9

Liberal - 5

Irish Nationalist - 2

Irish Labour - 1

[* Includes William Morrison, MP for Cirencester & Tewkesbury, who would be elected Speaker after the election]

Conservative/National Liberal/Ulster Unionist majority 17

May 1955:

Conservative - 284*

Labour - 243

National Liberal - 15

Ulster Unionist - 10

Liberal - 5

Sinn Féin - 2

[* Includes the sitting Speaker, Morrison, MP for Cirencester & Tewkesbury]

Conservative/National Liberal/Ulster Unionist majority 58

October 1959:

Conservative - 308*

Labour - 220

National Liberal - 14

Ulster Unionist - 12

Liberal - 5

[* Includes Harry Hylton-Foster, MP for Cities of London & Westminster, who would be elected Speaker after the election]

Conservative/National Liberal/Ulster Unionist majority 108

October 1964:

Labour - 274

Conservative - 262*

Ulster Unionist - 12

National Liberal - 6

Liberal - 5

[* Includes the sitting Speaker, Hylton-Foster, MP for Cities of London & Westminster]

Conservative/National Liberal/Ulster Unionist majority 0

An interesting result, with the sitting Government returned with exactly half the voting MPs. By-election chnages would have pushed the Government into a minority and the Liberals would hold the balance of power.

This is an era before the rise of Plaid Cymru, the Democratic Unionist Party and the Social Democratic & Labour Party, so MPs basically fell into 3 categories - Conservative & allies, Labour, Liberal. These days a party could go some way below an overall majority and theoretically still be able to govern as a minority, as long as the other parties didn't gang up. In the 1960s, if you lost your majority, the other main party would simply need Liberal support to oust you.

But who would be Prime Minister? In October 1963, Harold Macmillan resigned and the Conservative party chose Alec Douglas-Home as the new Prime Minister. The problem was that he was a member of the House of Lords, and so disclaimed his peerage under the Peerage Act 1963 and in a November 1963 by-election was elected MP for Kinross & West Perthshire, in Scotland.

So, in our scenario, he would have to contest a non-Scottish seat. Which one?

One that springs to mind is Luton, which had been vacant since the National Liberals' Charles Hill had resigned in June 1963 to become Chairman of the Independent Television Authority. So, Douglas-Home could have been the National Liberal candidate for Luton - but in the November 1963 by-election the seat was won by Labour's William Howie. In theory, Douglas-Home could then have found another seat to contest, but his authority would have been badly damaged.

Another option is a bit more leftfield. In June 1963, David Campbell, the Ulster Unionist MP for Belfast South, had died. How about Douglas-Home serving as Prime Minister while representing that seat? How different would Northern Ireland politics have been if there had been a Prime Minister sitting for a Belfast constituency? Or at the February 1974 general election, would Douglas-Home, as a holder of a Great Office of State (Foreign & Commonwealth Secretary) and a former Prime Minister, be the biggest scalp claimed by the Unionists opposed to the Sunningdale Agreement?

A third option is the safe one. In November 1963, Douglas-Home had John Hare, the MP for Sudbury & Woodbridge (whom he had appointed Chancellor of the Duchy of Lancaster), elevated to the peerage - and hence triggering a by-election. It could be a simple swap, with Douglas-Home able to stand in a safe Suffolk seat.

Now, you may have noticed that the earldom of Home is a title in the peerage of Scotland, not in the peerage of the United Kingdom, and assumed that Douglas-Home would not have been eligible to sit in the House of Lords if Scotland had been independent, so if he wanted a political career at Westminster he would already have had to be an MP. However, he also held the barony of Douglas in the peerage of the United Kingdom - in our scenario this would be the only peerage he would have to disclaim, and could remain Earl of Home while Prime Minister.

March 1966:

Labour - 318*

Conservative - 219

Ulster Unionist - 11

Liberal - 7

National Liberal - 3

Republican Labour - 1

[* Includes the sitting Speaker, Horace King, MP for Southampton Itchen]

Labour majority 76

How would this election have been triggered? Douglas-Home losing a vote of confidence and calling an election? Or Labour's Harold Wilson becoming Prime Minister through a deal with the Liberals and going for an early election for a real mandate?

This election is the National Liberals' last one, as will shortly be absorbed into the Conservative party.

June 1970:

Conservative - 299

Labour - 244*

Ulster Unionist - 8

Liberal - 3

Unity - 2

Republican Labour - 1

Protestant Unionist - 1

Independent Labour - 1

[* Includes the sitting Speaker, King, MP for Southampton Itchen]

Conservative/Ulster Unionist majority 56

February 1974:

Conservative - 276*

Labour - 261

Liberal - 11

Ulster Unionist - 7

Vanguard Unionist Progressive Party - 3

Plaid Cymru - 2

Democratic Labour - 1

Social Democratic & Labour Party - 1

Democratic Unionist Party - 1

Independent Labour - 1

[* Includes the sitting Speaker, Selwyn Lloyd, MP for Wirral]

Conservative "majority" -13 or Conservative/Liberal majority 9

In the real world, Labour's 19 seat advantage over the Conservatives in Scotland, as well as a strong showing by the Scottish National Party meant Labour had a 4-seat lead over the Conservatives in what was not just a hung Parliament but one where even a Labour/Liberal coalition would be a minority Government.

Without Scotland, the Conservatives - rather than Labour - would be the largest party, and a majority administration with the Liberals would have been numerically possible. The combined Labour and Liberal MPs would have been fewer than the Conservative tally.

You might wonder whether a Conservative/Ulster Unionist Government (majority 1) was possible. By this stage, due to the Sunningdale Agreement, relations between those parties broke down irretrievably, and in some seats Ulster Unionist fought Ulster Unionist, with all 11 Unionist seats being from MPs opposed to Sunningdale.

October 1974:

Labour - 278

Conservative - 261*

Liberal - 10

Ulster Unionist - 6

Vanguard Unionist Progressive Party - 3

Plaid Cymru - 3

Social Democratic & Labour Party - 1

Democratic Unionist Party - 1

Independent Republican - 1

[* Includes the sitting Speaker, Lloyd, MP for Wirral]

Labour "majority" -7 or Labour/Liberal majority 13

In the real world, Labour won this narrowly. Without their 25-seat Scottish lead over the Conservatives, Labour would be forced down to being the largest party in a hung Parliament - and there would be the first two hung Parliaments in a row since the January/February 1910 and December 1910 elections.

May 1979:

Conservative - 317

Labour - 225*

Liberal - 8

Ulster Unionist - 5

Democratic Unionist Party - 3

Plaid Cymru - 2

Social Democratic & Labour Party - 1

Independent Republican - 1

United Ulster Unionist - 1

Independent Unionist - 1

[* Includes the sitting Speaker, George Thomas, MP for Cardiff West]

Conservative majority 71

June 1983:

Conservative - 376*

Labour - 168

Liberal - 12

Ulster Unionist - 11

Democratic Unionist Party - 3

Social Democrat - 3

Plaid Cymru - 2

Social Democratic & Labour Party - 1

Sinn Féin - 1

Ulster Popular Unionist Party - 1

[* Includes Bernard Weatherill, MP for Croydon North East, who would be elected Speaker after the election]

Conservative majority 173

June 1987:

Conservative - 366*

Labour - 179

Liberal - 10

Ulster Unionist - 9

Democratic Unionist Party - 3

Social Democrat - 3

Plaid Cymru - 3

Social Democratic & Labour Party - 3

Sinn Féin - 1

Ulster Popular Unionist Party - 1

[* Includes the sitting Speaker, Weatherill, MP for Croydon North East]

Conservative majority 153

April 1992:

Conservative - 325

Labour - 222*

Liberal Democrat - 11

Ulster Unionist - 9

Plaid Cymru - 4

Social Democratic & Labour Party - 4

Democratic Unionist Party - 3

Ulster Popular Unionist Party - 1

[* Includes Betty Boothroyd, MP for West Bromwich West, who would be elected Speaker after the election]

Conservative majority 72

So, no nail-biting votes in the House of Commons and the Government manages a full 5 years without becoming a minority one.

This election was followed by the resignation of Neil Kinnock as Labour leader, and John Smith, then the Shadow Chancellor of the Exchequer, replacing him. But Smith sat for a Scottish seat.

If we look at the November 1991 elections to the Shadow Cabinet, then the top 3 - Shadow Trade & Industry Secretary Gordon Brown, Smith, and Shadow Health Secretary Robin Cook - all have Scottish seats. In fourth place is Ann Clwyd, then the Shadow Minister for Overseas Development.

With Smith unable to stand, is it too far fetched to think that Tony Blair becomes Leader of the Opposition two years early?

May 1997:

Labour - 363*

Conservative - 165

Liberal Democrat - 36

Ulster Unionist - 10

Plaid Cymru - 4

Social Democratic & Labour Party - 3

Democratic Unionist Party - 2

Sinn Féin - 2

UK Unionist Party - 1

Independent - 1

[* Includes the sitting Speaker, Boothroyd, MP for West Bromwich West]

Labour majority 138

In October 2000 Boothroyd resigns and is replaced by Michael Martin, Labour MP for Glasgow Springburn. Of course, if Scotland were independent, then Martin would not be Speaker.

June 2001:

Labour - 357

Conservaive - 165

Liberal Democrat - 42

Ulster Unionist - 6

Democratic Unionist Party - 5

Plaid Cymru - 4

Sinn Féin - 4

Social Democratic & Labour Party - 3

Kidderminster Hospital & Health Concern - 1

Labour majority 127

May 2005:

Labour - 315

Conservative - 197

Liberal Democrat - 51

Democratic Unionist Party - 9

Sinn Féin - 5

Plaid Cymru - 3

Social Democratic & Labour Party - 3

Ulster Unionist - 1

Kidderminster Hospital & Health Concern - 1

Respect - 1

Indpendent - 1

Labour majority 43

May 2010:

Conservative - 306*

Labour - 217

Liberal Democrat - 46

Democratic Unionist Party - 8

Sinn Féin - 5

Plaid Cymru - 3

Social Democratic & Labour Party - 3

Green - 1

Alliance Party of Northern Ireland - 1

Independent - 1

[* Includes the sitting Speaker, John Bercow, MP for Buckingham]

Conservative majority 20

The exclusion of Scotland would have altered the results of some close elections. The 1964 one would have been effectively a dead heat (if the Liberals supported Labour) or the return of a Conservative-led Government, instead of a Labour one.

The first 1974 one could have seen the Conservatives remain in power, rather than the return of Labour.

And 2010 would have seen the Conservatives govern alone.

One thing to note is that the 1945 election - not 1997 - would have been Labour's greatest electoral victory.

Why Is Easter In March?

A couple of evenings this week, those nice people at South West Trains cancelled the last train from Andover to Basingstoke, and put on every commuters' ultimate nightmare - the rail replacement bus service. Which stank. I think just beforehand it had been used to host a chainsmokers' convention.

Hence, I get to Basingstoke at 1/4 to midnight, hang around for a slow train to Southampton Central, get in about 20 to 1, no buses that late, and walk home.

Wednesday morning I was hurrying home and it was quite cloudy, with a full moon shining through a gap in the cloud.This wasn't any old full moon - this was the Paschal Full Moon, the first one of spring.

In an earlier post (keep it open in a new tab or window as I will refer to it later) I mentioned the calendar reform by Ugo Boncompagni which gave us the Gregorian calendar we all know and love today.

For the Roman Catholic Church it was/is important that Easter was celebrated on the right day.

In my previous post I looked at the different types of lunar months, and the important one for this is the synodic month of 29.530589 days.

The average year length in the Gregorian calendar is 365.2425 days. 19 years will be 6,939.6075 days on average. It depends how many leap years there are in those 19 years - there will be 4 or 5, so 19 years will be 6,939 or 6,940.

235 synodic months is 6,939.688415 days - very close to 19 years. So, if you have a full moon (or perhaps, the Paschal Full Moon) on a day one year, it is likely to be on the same day 19 years later. This is called the Metonic cycle.

The Jewish calendar is a luni-solar one, with most years having 12 months, but 7 out of every 19 having 13 months. Hence 235 months every 19 years.

If you have a copy of the 1662 Book of Common Prayer there will be tables about using the Golden Number to calculate Easter. The Golden Number is found by:

Take the year (2013)

Add 1 to it (2014)

Divide by 19 (106, remainder 0)

The Golden Number is the remainder - if the remainder is 0, then the Golden Number is 19.

So, this year has a Golden Number of 19. One table will give the Paschal Full Moon for each number (really an ecclesiastical Paschal Full Moon, as the real one could be a day different due to leap years). And we see the date given as 27 March - with Easter being the following Sunday (31 March).

12 synodic months is 354.367068 days, so if you have a full moon on one date one year, you should expect one about 11 days earlier the following year (if you onserve meteor showers, then it is best for the peak to be near new moon - useful advice I got once is that if a new moon is on a particular date one year, it should be on a near-enough date 3 years later). So, we should expect the Paschal Full Moon to be about 11 days earlier from year-to-year, so Easter should be about a week (or maybe a fortnight) earlier each year.

Except when you have an earlyish Paschal Full Moon, 13 synodic months is 383.897657 days, so you should then expect the Paschal Full Moon to jump about 19 days later the following year.

A Golden Number of 1 gives the Paschal Full Moon (ecclesiastical) as 14 April. This is a Monday, so Easter is the following Sunday - 20 April.

Actually, the real Full Moon is on 15 April, when there is a total lunar eclipse.

What was the problem that Boncompagni wanted to sort out?

The British Empire didn't switch from the Julian calendar to the Gregorian until 1782, and there is a dating convention of writing [OS] for "old style" for Julian calendar dates and [NS] for "new style" for Gregorian calendar dates.

The vernal equinox is often on 7 March[OS]/20 March[NS]. This year the full moon was 14 March[OS]/27 March[NS]. And this highlights what the problem was.

Under the Julian calendar, with an ecclesiastical vernal equinox remaining 21 March, this week's full moon was still a winter one.

The next full moon is 12 April[OS]/25 April[NS] - and under the old calendar this would be the Paschal one, the first of spring. And Easter would be 15 April[OS]/28 April [NS].

Hence, Boncompagni's problem that people could be celebrating Easter incorrectly as the Sunday after the second full moon of spring.

The Moon And The Month

[Another post in preparation for writing about Easter]

We were taught at primary school that the word "month" comes from "moon" - that a month is about the time that the moon takes to go round the Earth.

And this is an approximation.

But there are different types of month.

In my previous post (I suggest opening it in a new window or new tab as I will refer to it later) I had a look at the tropical year and the First Point of Aries. In stellar co-ordinate systems there is something called ecliptic longitude and ecliptic latitude. These are both zero at the First Point of Aries.

If you picture a line perpendicular to the ecliptic at the First Point of Aries (go back to the image of Pisces in the previous post) then anything along that line has an ecliptic longitude of zero.

The average time it takes for the Moon to return to an ecliptic longitude of zero is known as the Tropical month and this is 27.321582 days long.

New moon is when the Sun, Moon and Earth line up. You might think that one tropical month after new moon it would be new moon again, but this ignores that the Earth is in orbit around the Sun.

Suppose, for example, we have a new moon at precisely the vernal equinox. The Sun (at the First Point of Aries) and the Moon both have an ecliptic longitude of zero. One tropical month later, the Moon has an ecliptic longitude of zero. But the Sun?

Well, that's moved on, and by then would be just on the border of the neighbouring constellation Aries (all constellation images from Heavens Above:

So, the Moon has to catch up the Sun, which takes it a couple of extra days or so to do. This gives us the Synodic month of 29.530589 days, the average time from new moon to new moon.

These are not the only months. You'll notice I've been talking about the Moon having an ecliptic longitude of zero, rather than being at the First Point of Aries. If you recall the pictures of Pisces and Aquarius you would see five of the planets - Mercury, Venus, Mars, Uranus and Neptune - were near the ecliptic but not on it.

And the same is true for the Moon. For example, the northernmost part of the ecliptic - which will be where the Sun is at the summer solstice - lies in Gemini

Actually, it's only just in Gemini. It's very near the border with Taurus:

I recall recently walking home and seeing the Moon, and later realising it had actually been in Orion:

The ecliptic passes through 13 constellations (not 12) - but Orion isn't one of them! But the northern part of it (traditionally marking his club) is very close to the ecliptic - close enough to have the Moon passing through it briefly.

The full moon nearest to the winter solstice - the full moon that will be highest in the sky and above the horizon longest - will probably be in Gemini or Taurus. But if the Moon is near its furthest below the ecliptic then it could be in Orion. And if the Moon is near its furthest above the ecliptic it can be in Auriga:

We are all aware that north of the Arctic Circle there is the Midnight Sun. Well, in parts of the USA, Canada, Greenland, Iceland, Norway, Sweden, Finland and Russia south of the Arctic Circle you can at times have the Moon above the horizon for over a day - when it is to the north and at its lowest it is still above the horizon.

The Moon moves from below to above the ecliptic at its ascending node and from above to below at its descending node. The average time from ascending node to ascending node is the Draconic month and is 27.21222 days - shorter than both the tropical month and the synodic month. Hence, if there is a new moon at the ascending node (something I'll come back to in a moment), then at the next new moon, the Moon will be above the ecliptic.

After 242 draconic months - 6,585.35724 days - the Moon would again be at the ascending node. What's so special about this? 223 synodic months is 6,585.321347 days - just 52 minutes less than 242 draconic months.

Suppose there is a new moon with the Moon near a node, then the Moon is likely to be seen in front of the Sun - a solar eclipse. This close connection between 242 draconic months and 223 synodic months gives us the Saros cycle of a little over 18 years. If there is an eclipse one day, there will probably be one a Saros cycle later. The American total solar eclipse of August 2017 is one Saros later than the August 1999 one that I saw from Alderney.

What's Another Year?

[Note - this might seem a bit random, but I was drawing up a post on Easter and realised I would spend a lot of time on this, so decided to do it as a separate post]

We know that the year is 365 days long, but in a leap year there is an extra day (29 February). I'm quite pleased that a 29 February is so rare, as it is the only day that I dislocate my shoulder on.

The idea that every fourth year is a leap year isn't totally accurate, as the final year of a century is only a leap year if it can be divided by 400. The final year of last century (2000) was a leap year, but the final year of this century (2100) won't be.

Over a 400 year period, there will be 97 years with 366 days and 303 with 365 days. This is 146,097 days, so the average year length is 365.2425 days.

One year used by astronomers is the Tropical year, which is measured from vernal equinox (the start of the northern hemisphere spring) to vernal equinox.

The image - taken for today from Heavens Above shows the constellation of Pisces, in which we find the First Point of Aries.You can find the First Point of Aries by looking for the 0 hours along the x-axis and the 0 degrees along the y-axis and seeing where they cross. At that point - the First Point of Aries - you will see an inclined white line cross. That is known as the ecliptic and marks the path of the Sun in the sky. You will see that the Sun does, indeed, lie on the line, and there are 3 planets (Venus, Mars and Uranus) near the Sun and near that line. You can also make out Mercury, down in neighbouring Aquarius:

If you're in the tropics or the southern hemisphere then Mercury is an impressive object in the pre-dawn sky at the moment.

The Sun is at the First Point of Aries at the vernal equinox.

The tropical year is 365.2421897 days long. The old Julian calendar simply had every fourth year a leap year, but something happened when the average year was 365.25 days long.

We can see that the difference between the average Julian year and the tropical year is 0.0078103 days, which might not seem much (it's just over 11 minutes). Over a century this becomes 0.78103 days - which is 18 hours 45 minutes. So, each year, spring was starting earlier.

In May 1572 Ugo Boncompagni became Pope Gregory XIII and one task he set about was calendar reform. This might seem an odd thing for the Vatican to be worried about, but it has all to do with getting Easter right.

In 1582 he took the papal bull by the horns and decided to abolish the days from 5 to 14 October inclusive (for that year only), so 4 October was followed by 15 October.

Abolishing days is one of the perks of being Pope - yet not one of them has abolished Monday mornings.

Boncompagni also altered the rules concerning end-of-century years always being leap years, and so brought the average year length closer to the tropical year. The average year is now 0.0003103 days longer than the tropical year, and over 400 years this amounts to 0.12412 days - just under 2 hours 59 minutes. So, after 4 centuries, spring is starting a little bit less than 3 hours earlier.