When I was a young child, I had a friend born on February 29, the “Jump Day” that we add to that month every four years. I remember that we were used to adding it by saying that he was only three years old. I lost his contact with him over the years, but I think he is now very sick from the joke.
Here we are again on the threshold of our quadruple exercise in time: a jump on 2024 on us. A handful of tradition was associated with it; Someone saw that this is the only acceptable day for – GASP! Some people love to deal with this day as a free day that gives them time to catch up with something long.
I think this is a good idea because catching a knee is what is going on on the day of jumping – economically, that is.
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There are two basic units for the time we use dependent on astronomical events. The first is today, the length of time it takes the Earth to spin once on its axis. The other is the year, and the time that the Earth takes to complete the orbit of the sun. While this seems simple, these two units are actually complex. For example, the Earth rotates once for what? You need some reference frame to measure this movement.
For our daily lives, we use the sun. The time the sun takes in the south in the south and then rises again and gets to the southern length line again is one solar day, which we determine over 24 hours, or 86400 seconds. This is actually Intended The solar day, which uses the sun’s disk center as a reference point and is average every day of the year. The use of medium value is useful to save time because the Earth moves at different speeds at different points in its orbit, which changes the exact length of any specific day.
There are several different ways to measure the length of the year as well. Our current calendar uses the tropical year, and the time of moderation in the era to the spring moderation, to calculate hidden effects such as accuracy. Otherwise, the date of moderation will change slowly over the years, and in the end the coup will occur in December in July, which will be very confusing.
A tropical year is 365,2422 average solar energy days in length. Since the rotation of the earth and the orbital period are not associated with any way, it is not equally divided. We left with the rest 0.2422, and this is the key to jumping days.
If we start to measure today and the year at the exact moment, the Earth will be at the end of one year that has woven 365 times, in addition to 0.242 of the road at the start of the new year. After four years, this adds up to 0.9688 days – almost a full day. We built an additional day in the year!
This was known even for the ancient peoples, and when Julius Caesar decided to change the basis of the Roman calendar from using the moon to the sun, he also decided that every fourth year an additional day will be added to keep everything simultaneously. Congrats! A happy day! This technically is called Intercalary, which is added to the calendar for its synchronization.
With the exception of mathematics, it does not succeed completely. By adding a full day every four years, we add a lot: after four years, only 0.9688 days remain, not 1.0 days. This difference is 0.0312 days, or about 45 minutes. This means every four years we still have about three quarters of an hour for its account. Over time, this will accumulate, and the calendar will be stopped again.
Pope Gregory XIII, who fixed the calendar again in 1582. He decided that every year a hundred (to make it simple, ends at 00) no Be a year jumped, so a leap day will not be added. There are 25 days a jump in a century, so this method Remove 25 x 0.0312 = 0.78 days, and the calendar coincides slightly better in the long run – but again, not exactly.
Using this algorithm, every 100 years the calendar will run from 1 to 0.78 = 0.22 days. This adds, too! As part of his papal revolution, Pope Gregory XIII also announced that every year 400 will again get a day jumped. By that time, there are 4 x 0.22 = 0.88 days, so adding one day makes us close to catching an annual unattractive back of the ground.
This is the rule that we use now. Every year, in the sense of each year its number is equal to 4 years, is a jump year and gives an additional day – that is, except for every 100 years, when we skip the day of jumping, Excluded For every 400 years, when we reflect the base and one day add a jump again. So the years 1700, 1800 and 1900 did not jump years. It was 2000 because although it was equally divisible by 100, it could be divided evenly by 400 years. The year 2100 will not have jumped, but the year 2400 will be, and so on.
This actually makes us close to synchronization. Sometimes I wondered, though, why Pope Gregory XIII did not use the time period for every 500 years instead of 400. This will be better because the remaining amount after 100 years is closer to five of the day. But here we are.
For this reason, though, our current rules still leave the calendar a little. We add a full day every 400 years, but this is more than 1 – 0.88 = 0.12 days. If we want it, we can adjust the base again and say that every 3200 years, we no Make that year a jump year. Why 3200? Well, 8 x 0.12 = 0.96, so that we can skip a year of jumping every 400 -year -old, which is every 3200 years. This means that the year and today will only be stopped by 0.04 days – less than an hour – every three thousand years, and it is very close.
As usual, when dealing with astronomy, numbers and evaluation, things seem simple – not to be.
However, the day of a happy jump, and if you have something that has been postponed for four years, it is now good like any time to reach it. And to my old friend Ted, if you are there and spoke to see this: Happy Birthday!