On December 21st, just after sunset, Jupiter and Saturn will be visible just 6’ apart. This very close conjunction was last seen in 1623. Even if you can’t see them on the 21st, you can still see them very close together on the few days either side of the 21st. On the 17th they will 28’ apart on the 23rd they will be separated by 14’.
The image below shows them on the 21st at 17:00GMT from Abingdon.
The down side is that they will be very low, not even 10 degrees above the horizon, so you will need good clear horizon to see them.
The Geminid meteor show peaks on the 13th December this year at around 20:00GMT. This year should be a good opportunity to see them as the Moon will be out of the way. Expect some bright meteors and the potential of up to 100 meteors an hour.
As the picture shows the meteors will appear to originate from the constellation of Gemini. But it is best to look to the East or West of the radiant. If you look at it the meteor trails will be foreshortened due to perspective so look to the East or West of the constellation to see longer trails.
The Leonid meteor show peaks on the night of the 17th/18th November this year. There will be no Moon to spoil the view and hopefully no clouds either! The radiant will clear the horizon about 10:30UT, but The actual peak in activity is expected around 05:00UT of the 18th (see the chart below). Observed rates are in the region of 10 to 15 per hour.