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28-29 February 2020 – “Speaking with the Stars”: Tonight at twilight, Bella Luna in her waxing crescent phase forms a triangle with Venus the Goddess of Love, & the brightest stars of Aries. Then later when the rest of the stars come out, look above the Moon to see the 7 Sisters of the Pleiades. Helping to guide you, will be orange Aldebaran.

Tomorrow dear friends, we get a bonus day – What will you do with it?

Saturday, 29 February 2020 is leap day, that calendar oddity that occurs (almost) every four years. For centuries, attempts to sync up with the length of the natural year have sowed chaos—until the concept of leap year provided a way to make up for lost time. Human beings have struggled to align civil, religious, & agricultural calendars with the solar year, so adding a ‘leap year’ solved the problem—although just for the next 3,300 years.

The solar year is approximately 365.2422 days long. No calendar day can match that number, & simply ignoring the seemingly small fraction creates a much bigger problem done the line.

In the past we human beings organized our lives in accordance with what we observed in the skies, this is the principle behind Sidereal astrology. For instance, ancient Egyptians planted their crops each year on the day when Sirius appeared. Ancient Greece & Rome also relied on the positions of the stars to anchor Festivals & other events in time.

Image result for ancient egyptian calendar

Early Egyptians (prior to about 3100 B.C.) & other societies from China to Rome once used lunar calendars to track time. But lunar months average 29.5 days & so the year only adds up to about 354. So societies that kept lunar time quickly drifted well out of sync with the seasons due to the 11-day lag.

Image result for ancient sumerian ancient mesopotamian calendar

Other ancient calendars, like the Sumerians, dating to around 5,000 years ago, simply divided the year into 12 months of 30 days each. Their 360-day year was nearly a week shorter than our annual journey around the sun. The practice of adding extra days to the year is at least as old as these systems.

When the Egyptians adopted this calendar they were aware that there was a problem – but they solved it by adding in an extra five days of partying – in the form of festivals, at the end of the year.

Religious leaders expected feast days to align with certain seasons & lunar phases. That’s why most of the modern world has adopted the Gregorian calendar & its leap year system to allow days & months to stay in step with the seasons.

Image result for caesar cleopatra painting

By the time Julius Caesar enjoyed his famed affair with Cleopatra, Rome’s lunar calendar had diverged from the seasons by some three months—despite efforts to tweak it by irregularly adding days or months to the year.

To restore order, Caesar looked to Egypt’s 365-day year, which as early as the third-century B.C. had established the utility of a leap-year system to correct the calendar every four years.

Image result for Caesar 445-day-long Year of Confusion (46 B.C.)

Caesar adopted the system by decreeing a single, 445-day-long Year of Confusion (46 B.C.) to correct the long years of drift in one go. He then mandated a 365.25 day year that simply added a leap day every fourth year.

But even this system was flawed, because the quarter of a day that leap year adds annually is a bit longer than the solar year’s leftover 0.242 day. That made the calendar year some 11 minutes shorter than its solar counterpart, so the two diverged by an entire day every 128 years.

Between the time Caesar introduced the system & the 16th century, this small discrepancy had caused important dates, including the Christian holidays, to drift by some 10 days.

Image result for Pope Gregory XIIIGregorian calendar

Pope Gregory XIII found the situation untenable, so his Gregorian calendar was unveiled in 1582—after another drastic adoption of time-warp tactics.

Gregory reformed the calendar & they dropped ten days from the month of October that year. Then they changed the leap day rules to correct the problem.

Now leap years divisible by 100, like the year 1900, are skipped unless they’re also divisible by 400, like the year 2000, in which case they’re observed. Nobody alive remembers the last lost leap day, but dropping those three leap days every 400 years keeps the calendar on time.

Even today, some calendars discount the leap year meant to keep us in time with our orbit, while others ignore the sun altogether.

Image result for ancient Islamic calendar

The Islamic calendar is a lunar system that adds up to only 354 days & shifts some 11 days from the Gregorian calendar each year—though a single leap day is sometimes added.

And while China uses the Gregorian calendar for official purposes, a traditional luni-solar calendar is still popular in everyday life. It follows the phases of the moon & implements an entire leap month about once every three years.

People can get used to any calendar system. But once they are used to it what really seems to rile them up is when something is changed. This is why ‘daylight saving time’ is so controversial.

The current Gregorian calendar system makes the fractional days of the solar year & leap year calendar nearly equal by occasionally skipping a leap day.

This system produces an average year length of 365.2425 days, just half a minute longer than the solar year. At such a rate it will take 3,300 years before the Gregorian calendar moves even a day from our seasonal cycle. That means future generations will eventually have a decision to make on leap year. So dear friends, 3,000 years from now, folks may need to decide to tweak it. We’ll just have to wait & see.