Last week was Autumn Equinox, when day and night are twelve hours each. Few people realize, though, it’s also the time when the day shortens most quickly. Indeed, here in London, the day was a full 3 minutes and 54 seconds shorter on September 25st than it was the day before. This change adds up: in the month around the equinox, our days will have shortened by almost two hours. You can see this change here:
Even if we haven’t spent time on http://www.timeanddate.com/ pondering the length of the day, subconsciously we all are aware that something has been going on recently. Perhaps we have found ourselves thinking more urgently about all that lies before us. During the lazy days around June’s summer solstice, when day length narrows by less than a second each day, time feels endless. But now, when the sun creeps through our curtains a couple of minutes later each morning, we viscerally sense the passage of time.
p.s. Ok, I’m not an astronomer, and it be that the equinox is not actually the fastest-changing day, but a few days before/after it.
p.p.s. And for those of you in the Southern Hemisphere, enjoy the coming summer!