D E C E M B E R

SKY WATCH

The moon is back in play and Sirus brings in the New Year

New Moon 4th December

The new moon arrives on 4th December and by the evening of 6th December the new waxing crescent moon will be back in the evening sky. From then through to 9th December (cloudless skies permitting) you can see beautiful scenes after dark as the moon moves away from the sun and first passes Venus, then Saturn, then Jupiter. Two of these (Venus and Jupiter) are the brightest planets. They will be very noticeable with the moon. The moon itself, should be showing some mysterious markings!

Full Moon 19th December

Full moon is due on 19th December. This will be the last full moon of the Northern Hemisphere’s autumn and the Southern Hemisphere’s springtime. It is also the last full moon of 2021 and it’s the closest full moon to the December solstice.

This full moon happens one day after the moon reaches the farthest point in its orbit around Earth. It is 400,000km away and as a result is measurably smaller in the sky than usual. Although you probably won’t notice any difference December’s full moon is the opposite of a Super Moon.

Winter Solstice 21st December

At the winter solstice, the sun reaches its most southerly point in the sky for this year. So the Northern Hemisphere has its shortest day and longest night of the year and the Southern Hemisphere has its longest day and shortest night. It’s a milestone in Earth’s orbit and a marker of seasonal change.

The moment of the solstice will occur at 15.59 on 21st December in the UK. The shortest day will last around 7hrs 49 mins which makes it around 8hrs 48mins shorter than at Summer Solstice.

Today, people visit the ancient site of Stonehenge to celebrate the winter and summer solstice. One reason why this is a popular site to visit is that you can glimpse the sun’s rays through the stones which are lined up with the path of the sun. While both solstices are celebrated the ancient civilisation that first built the monument most likely did so primarily for the winter solstice, perhaps to request a good growing season in the year to come. (Source: National Maritime Museum, Greenwich, London)

Sirius New Year's Eve

The star Sirius is the brightest star in the sky. The three Belt stars in the easily recognisable constellation of Orion, the Hunter point to it. Sirius also has the nickname the Dog Star because it’s part of the constellation Canis Major the Greater Dog. On New Year’s Eve you can entertain your guests with a glass of bubbly and see in the New Year with a Sirius reaching its highest point around midnight.