Solstice signals astronomical winter
The winter solstice took place at 23:03 UTC on 21 December. The disc seen from Meteosat was mostly dark at the exact time of the solstice.
From the solstice onwards, Europe makes its way back towards the longer days and shorter nights of summer. In meteorological terms, it has already been winter for some weeks, but the solstice signals the start of the astronomical winter.
In the southern hemisphere, things are much brighter in December. These images from Meteosat show how the disc it pictures changes with the solstices and equinoxes each year:
You can read more about solstices seen from space here.
The solstice was a very important time for ancient tribes who tracked the progress of the seasons and the placement of the Sun in the sky. Celebrations are held at ancient monuments like Stonehenge in the United Kingdom, and Newgrange in Ireland. Newgrange is a passage grave and on the mornings around the solstice, the rising Sun shines in to illuminate an interior chamber.
However, the difference between clock time and sun time means that the shortest day does not necessarily have the earliest sunset.