Humanity’s ongoing quest for the perfect calendar

☀️ Today is the summer solstice (AKA the longest day of the year and the first day of summer), which is when the North Pole is most pointed toward the sun
Issue #102: glass children, elderly homelessness, and the flames that shape us
By Carly Rose Gillis

If June 20 seems a bit earlier to you than usual for the summer solstice, you are right — occurring at 20:51 UTC, this will be the earliest solstice since 1796, when George Washington was president.

To explain this, astrophysicist Ethan Siegel broke down the fascinating history of our calendaring system, which has always been in flux because our 24ish-hour days just can not fit neatly into Earth’s 365ish-day orbit.

The first commonly accepted calendaring system was lunar, which used the moon’s consistent cycle of approximately 29.5 days (from new moon to new moon) to define a month. It worked well because about 12 of those cycles (which equals 354ish days) approximately lined up with a full orbit (365ish days). To keep the seasons consistent (and lined up with the actual position of the Earth in its orbit), a 13th month was added every three years to course correct for that yearly shortage, called an “intercalary” month.

But when Rome became a world power, these intercalary months became political. High priests started arbitrarily doling out intercalary months based on who they wanted to stay in power for longer. This became too chaotic, so the Julian calendar (decreed by Julius Caesar in 45 BC) came to everyone’s rescue and relief by using the sun instead of the moon to measure a year, ushering in our current 365ish-day year (and introducing leap days every four years).

But still, things weren’t perfect in calendar land! Siegel explains:

That difference between the ‘true value’ of 365.242189 days in a year and the ‘assigned’ value of 365.25 days in a year results in a mismatch of just under one day per century. By the middle of the second millennium, solstices and equinoxes were occurring in the first half of March, June, September and December, rather than on their original dates.

Enter: the Gregorian calendar in 1582. It fixed the Julian calendar’s calculation error by deleting 10 days (October 4, 1582 was followed by October 15, 1582) and by creating an additional leap year rule: “if the year ended in ‘00’ (i.e., was a turn-of-the-century year), it must also be divisible by 400 to remain a leap year. The year 2000, which is both divisible by 4 and 400, was a leap year, but the years 1900, 1800, and 1700 were not.” Fewer leap years means less drifting of the solstices and equinoxes (but still, not perfect).

Our summer solstice will continue to happen earlier in June each leap year until the next skipped leap year (2100). See you then?!

What else we’re reading

• The term “glass children” refers to the siblings of chronically ill kids, whose needs often get overlooked as their parents see right past them, as if they were made of glass. What’s the best form of support for these kids? As writer John Grewell explains, it involves countering the isolation of their lived experience with socialization and peer-to-peer support.
• In “If Boomers Had It So Good, Why Are They Greeters At Walmart?” Linda Caroll contributes some scathing commentary about the state of elderly homelessness, and includes this shocking statistic: “The average worker in America will earn $1.7 million in a lifetime of working. Bezos earns that in less than 15 minutes.”

Your daily dose of practical wisdom: for when you feel like the world is on fire

A writer on Medium shares a metaphor comparing times of crisis as living in a burning house that can help:

So if you grow up in a burning house, remember this; the whole world is not on fire. There are places of peace, moments of calm, and people who will help you heal. The flames may have shaped you, but they don’t have to define you.

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Edited and produced by Scott Lamb & Harris Sockel

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