In the March Mathness post I mentioned that one reason I love March is that it contains the Vernal Equinox, the official astronomical start of Spring. More importantly to me, it means six months of more daylight than darkness, and as much as I’m a night person, I prefer long, sunny days.
Well, today is the day! The equinox happened at 21:58 UTC (two minutes before 5:00 PM locally). What’s better is that, after all the miserable bitter cold and all that snow in February and into March, the weather is indeed finally turning. Deeply embedded in our mythologies is the idea of spring rebirth; New Year’s parties aside, this, today, is the true new year.
And the forecast is for muon showers!
It’s officially fall, the season named after what the leaves are doing now (at least in places where they came up with the word, “fall”). Did you ever notice how the two seasons of transition both are named after action verbs? Or how appropriate those verbs are to the cycle of life happening in those transitions? Life springs forth to sunny summer and falls asleep to weather winter.
The autumnal equinox was at 08:21 UTC. Here in middle America, by a standard we call “Central,” summer fell at 3:21 AM. I slept through it, so I didn’t hear any noise it might have made. (Sometimes you can hear a distant thud, but that might be a whole bunch of leaves coincidentally all falling at once.)
Today also marks the final dozen (exciting!) games for my Minnesota Twins!
It’s Friday, and I’m sure you’re thinking about the weekend, so today will be just a review and some more details about the speed of light.
And speaking of light, today is the Vernal Equinox. For the next six months (for those of us in the northern hemisphere), our days will be longer than our nights. No doubt the combination of spring, the Equinox, and the weekend, have you wondering what you’re doing at your computer reading about Special Relativity.
So I’ll try to be very brief…
Ever looping, ever spinning,
Passes a point.
Ever higher, ever warmer,
Melts all the snow.
Ever turning, ever changing,
Brings forth fresh life.
Winter’s silence fades.
Birds sing, life renews.
A new year begins.
Those who know me know that I’m not big on calendar holidays. Even my birthday tends to pass without fanfare. That comes from being single, the island that supposedly no one is. After a lifetime of Christmas and New Years’ being ordinary days, you get used to it.
But I do honor the Solar Event Days because (as I’ve mentioned many times) light is so important to me (and because I’m a geek). Christmas may not mean much to me, but the Winter Solstice does! The days finally start getting longer! Summer Solstice is a day of mourning for the opposite reason.
Today — the Autumnal Equinox — marks the halfway point.
Tonight’s sky holds a half-moon that looks somewhat like the picture on the right. Can you tell me, just by the picture, is the moon getting bigger or getting smaller?
Of course the moon isn’t really changing size. We use the shorthand “bigger” and “smaller” to refer to how much of the moon we see. Or more properly, how much of the moon is illuminated by the sun. Or even more properly, how much of the moon’s surface facing the Earth is illuminated by the sun.
You can see why we often just say it’s getting “bigger” or “smaller!” Or we can use the terms waxing (getting bigger) and waning (getting smaller).
So can you tell, from the picture, is the moon tonight waxing or waning?