Today, December 21, is the winter solstice. In the northern hemisphere it's the shortest day of the year. Various cultures have, for thousands of years, marked the date scientifically and attached cultural significance to it. Typically the meaning involves the height of chill and darkness and the start of warmth and light returning. I attach to it the simple practical fact that it means the days will start getting longer now. I hate it being dark in the morning, dark again at 5pm, and pitch black by 7pm.
At least here in Silicon Valley, at latitude 37.4° N, the shortest day still provides 9.5 hours of daylight. ...Well, 9.5 hours of potential daylight. In the winter the sky here is typically overcast. We actually had
a lot of partly-sunny and mild weather through November up to mid-December, before it turned cooler and rainy this week. But even so, the 9.5 hours of daylight here is better than in, say, Helsinki, Finland at just past 60° N latitude, where the day lasts not quite 6 hours. And tomorrow night we're leaving for Sydney, Australia, where it's not even winter. In fact they just had their summer solstice with daylight stretching nearly 14.5 hours. I'm looking forward to a midwinter week of summer!