Pale light on leap day

The coming Thursday will not be March 1, as it would be in a common year. It will be February 29, a leap day, because 2024 is a leap year.

In this diagram from Astronomical Calendar 2024, darker blue indicates days with less moonlight in the following night. The Moon is full on Feb. 24, waning on Feb. 29.

The extra or “intercalary” day comes in each 4th year. If you were born on 2004 Feb. 29, on Thursday you will become just 5 years old, right?

And, in a leap year, light at its speed of 186,282 miles per second travels one day farther. So a light year is 366/365 times longer, right?

A cartoon from the “webcomic” Xkcd (sent to me at electronic speed by a friend 5,400 miles away) shows astronomers worrying about whether they have the right number for the distance to the nearest star. “Astronomers hate leap years because they make light-years 0.27% longer. When Pope Gregory XIII briefly shortened the light-year in 1582, it led to navigational chaos and the loss of several Papal starships.”

What worries me about light-years, and leap-years, is whether to put the hyphen in them.

And what I like about leap years is that I only have to blog about them in each fourth year. So for more information you can leap-frog back to 2016, or, much fuller, to the 550-word “leap-day” entry in our glossary book, Albedo to Zodiac.

May this be the day in which you make a Great Leap Forward in achieving some, at least, of the goals in your to-do list! A happy leap, not a disastrous Great Leap Forward like China’s in 1958.

__________

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