TIME: While it’s still almost three weeks until the shortest day of the year, look for the earliest sunsets in Bradford this coming week.

According to sunrise-sunset.org, the earliest sunsets — “the instant when the trailing edge of the Sun stops being visible and disappears below the western horizon in the evening” — will happen on Wednesday and Thursday, when the sun will set at 4:43:17 p.m. both days.

The latest sunrises of 2016 were back in January, but the latest sunrises of the 2016-17 winter season will be in early January 2017. Look for them on Jan. 2 and 3, when sunrise-sunset.org indicates the moment of sunrise — “the exact instant at which the upper edge of the Sun becomes visible over the eastern horizon, in the morning” — won’t happen until 7:42:31 a.m.

“It’s important to note that both sunrise and sunset are ‘instants,’ according to sunrise-sunset.org. “The time range during which the day becomes night or vice versa is called twilight.”

According to EarthSky.org, the winter solstice will occur at 5:44 a.m. in Bradford time on Dec. 21. This will be the shortest day of the year, as well as the calendar start of winter.

The solstice is another “instant,” EarthSky.org indicates: “It’s when the sun on our sky’s dome reaches its farthest southward pointward for the year.” This is from an article titled “Everything You Need to Know: December Solstice 2016.”

And it’s the tilt that causes the seasons.

“At the December solstice, Earth is positioned in its orbit so that the sun stays below the north pole horizon,” the article reads. “As seen from 23-and-a-half degrees south of the equator, at the imaginary line encircling the globe known as the Tropic of Capricorn, the sun shines directly overhead at noon.”

Besides the change in day and night length, another sign you will see in the northern hemisphere is that this is the time of year when your noontime shadow will be longest.