The big old world keeps spinnin' round

by Thom Barker

It happens every year. It happens so gradually we barely notice. We barely notice until that one day--usually in late January for me for some reason--when you look out the window and think it must be about 4:30 in the afternoon, but then look at the clock and discover it's after 6:00. The days are getting longer, my friends.

Yesterday was 8 hours, 59 minutes and 40 seconds long compared to the shortest day of this winter, December 21, which was only 7 hours, 42 minutes and 47 seconds long. Technically, the sun set at 5:50 on January 30, but when I went outside at 6:10, it was still light, and I experienced a sense of elation that seemed somewhat out of proportion with what seems such a common and mundane thing.

But it's not just the fact we are getting more sunshine moving inexorably toward the summer solstice--when we will see a glorious 16 hours, 45 minutes and 59 seconds of daylight--that always fuels my wonderment. We all know why there is such a variation in the length of our days, kind of, but we rarely think about what's really happening here.

The Earth is spinning, of course, which gives us day and night. We tend to think of it as a slow rotation, but it's actually moving at more than 1,600 kilometres per hour. It's also wobbling--what scientist call precession and nutation--so that an imaginary axis through the poles would ascribe, every 18.6 years, a small circle with loops defining the circumference. Don't care? Okay, how about the fact that we are, at the same time orbiting the sun at a rate of more than 100,000 kilometres per hour and the Sun, the solar system and all of our neighbouring stars and their systems out here on the periphery of the Milky Way are orbiting the galaxy's centre at approximately 9.4 billion kilometres per hour. Give or take. Like precision matters at this point. But that's not the end of it. The Milky Way itself and everything else in the universe is expanding at the speed of light--does anybody else hear a Monty Python song in their head?--and accelerating--yes, there is evidence that the constant is not constant. Wow, now my head is spinning and wobbling and orbiting and accelerating, figuratively as well as literally.

Funny how a seemingly little thing like a few extra minutes of daylight can lead to such mind-boggling ruminations. But what does it all mean?

It means the days are getting longer, my friends. The days are getting longer.