Winter has begun: Why it’s the shortest season of them all

A look at the winter solstice and what it means

Seasons. (NWS)

Did you miss it? 

At 10:58 this morning, the earth’s northern hemisphere (where you and I live) reached the point in our planet’s annual trip around the sun where we are tilted farthest away from our star. 

That moment is called the winter solstice, which makes today the day in which the sun’s midday position in the sky is at its lowest altitude of the year above the horizon. 

That also makes today the day with the least amount of daylight for the entire year (9 hours, 5 minutes) due to the sun’s shortest path across our northern hemisphere sky.  So after today, we start getting more daylight!  Naturally, the increase is incremental at first…you won’t notice it.  But in just a few weeks you’ll certainly notice the later sunsets.

But did you know that astronomical winter, which officially began at 10:58 this morning, is also our shortest season of the year? There’s a reason for that.

More: Science news

Most people don’t know that Earth’s orbit around the sun is not a perfect circle…it’s an ellipse.  And believe it or not, we are actually closest to the sun during the winter, and farthest during the summer! 

That’s important due to some physics:  as the earth travels around the sun, it moves a little faster when it’s closer to the sun, and a little slower when it’s farther from the sun.

So, since we’re closest to the sun during the winter, the earth’s orbital speed is fastest during this season, so the time between the winter solstice and the vernal equinox (first day of spring) is actually almost five days shorter than it takes the earth to get from the summer solstice (first day of summer) to the autumnal equinox (first day of fall).

So there you have it: today marks the start of the year’s shortest season!

Related: Winter solstice starts Dec. 21 -- here’s a quick explanation


About the Author:

Local 4 meteorologist Paul Gross was born in Detroit and has spent his entire life and career right here in southeast Michigan. Paul has researched, written and produced eight half-hour documentaries for WDIV, as well as many science, historical and environmental stories.