Why isn't the earliest sunset on the shortest day?

The numbers

In all three cities the shortest day is 21 December, the winter solstice (21 December 2026 in UTC). The earliest sunset comes well before it and the latest sunrise well after.

Why it happens

The length of the day is set by the tilt of the Earth's axis, and it is shortest at the solstice. But the middle of the day — solar noon, when the sun is highest — is not always at the same clock time. Around December it gets about half a minute later every day.

That drift comes from two things. The Earth's orbit is an ellipse, and in early January we are at the closest point to the Sun and moving fastest, so the Earth has to turn a little extra each day to bring the Sun back to the same place in the sky. And near the solstices the Sun's yearly path across the sky runs parallel to the equator, so all of its daily eastward drift counts towards delaying noon — near the equinoxes, part of that drift is northward or southward instead. Astronomers call the difference between sun time and clock time the equation of time.

So in December the whole day slides later on the clock while it is also getting shorter. Before the solstice the slide is enough to make sunsets later even though days are still shrinking; after it, sunrises keep getting later for a while even though days are growing.

In the southern hemisphere

The same thing happens in June. In Sydney the earliest sunset is on 12 June 2026 (4:52 pm), the shortest day on 21 June 2026 and the latest sunrise on 30 June 2026 (7:01 am).