James Abbott of North Essex Astronomical Society explains what to look for in the sky above Essex this December.

The ‘shortest day’ – the winter solstice - arrives on December 21 - the exact moment being at 9.21am.

From our latitude there is 12 hours of full darkness (ie excluding twilight) from 6pm to 6am.  

With the short hours of daylight, throughout December sunset is before 4pm and in early evening twilight, Venus will be visible, low down in the south west.

On the 4th and 5th , the young crescent moon will be near to Venus in the sky.

As the month progresses, Venus will become steadily more prominent and by the last week of December, Venus will take on the role of the ‘Christmas star’, a brilliant object visible against a dark sky after twilight has ended.

Jupiter rules the rest of the night. The gas giant planet is at ‘Opposition’ on December 7, the date on which it is exactly opposite the sun in the sky and hence visible all night.

The full moon will pass by Jupiter on the night of the 14th/15th.

Mars continues to brighten and by the end of the month is rivalling the brightest star in the sky, which is Sirius.

The map shows the view looking south at midnight in the Christmas week.

Using the constellation of Orion as a guide, Sirius is down to its lower left and the constellation of Taurus, including Jupiter, can be found to its upper right.

To the upper left of Orion is Gemini, and to the left of that, Mars, which shows an obvious reddish colour.

This complete view of the ‘winter’ constellations includes many bright stars which show colour to the unaided eye.

Unlike with planets, star colours relate directly to their surface temperatures – the more blue, the hotter, the more red, the cooler.

Viewing the winter constellations though a good pair of binoculars on a clear winter night (warm clothing recommended !) is well worth the effort.

There are many star clusters to be found and just below the three stars that make up the ‘belt’ of Orion is the Orion Nebula.

It is a huge complex of gas and dust where young stars are forming and its overall curved shape can clearly be seen in binoculars or a small telescope.

The most active meteor shower of the year is the Geminids, which peak just before the middle of December.

This year that unfortunately coincides with the full moon period, but some of the brighter meteors might still be seen.