If the Earth actually takes 23h56m to do a complete rotation aren’t we incorrectly shifting the days 4 minutes every day?

Question

Same for the years. If a year actually is 365.24219 days (tropical year) and we’re adding 1 day every 4 years (.25 per year) there’s a difference of 0.00781 days or ~11 minutes per year. After a few years, aren’t we actually shifting hours? Is there a mechanism to adjust it?

In: Physics

Answer 1

You’re right that adding a leap day every four years adds ever-so-slightly too much time. This is accounted for by skipping the leap day in years that are multiples of 100. That’s a lot closer, but then we’re actually adding slightly too little time, so if the year is multiple of 400, then we do have a leap year. At that point, we’re close enough for it not to matter at all.