Monday 20th to Sunday 26th December 2021
On Tuesday 21st at 3.59pm in the afternoon, the centre of the Sun's disc will reach its lowest position in the sky relative to the stars - this is called the Winter Solstice in the Northern Hemisphere, or in simple terms, the shortest day of the year - every evening after that it will stay progressively lighter a bit longer by almost four minutes. This is because the Earth actually takes 23 hours 56 minutes and 4 seconds to rotate, but we round it up to 24 hours to make it easier to read a clock!
The late evening of Wednesday 22nd sees the peak of the Ursids meteor shower, so named because the radiant point where the shooting stars appear to originate from is in the constellation of Ursa Minor, near the star Kochab. Around 11pm, you'll need to be looking towards the north.
The meteors are debris from comet 8P/Tuttle and they are travelling at around 70 kilometers per second when they hit our atmosphere and vaporise! The Ursids is not one of the largest meteor showers and only produces typically 10 per hour.
Talking about things that are going really fast, I have received a tip-off that Father Christmas will be doing a secret test run of his sleigh with the reindeer on the early morning of Thursday 23rd. Because he is travelling so fast, the sleigh will look like a moving bright light. It is due to be appearing in the south west at 6.47am and will take about seven minutes to pass overhead, before disappearing to the east. If all goes well, then he will be ready to deliver presents on Christmas Day.
On that note, it just remains for me to wish all our listeners a Happy Christmas and clear skies in 2022.
Screenshot courtesy of Stellarium
Copyright Adrian Dening and Radio Ninesprings 2021