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Sun, 11 Dec 2016 - Geminid maximum battles the Full Moon

Observing the peak of the Geminid meteor shower this month will be tricky.

The December weather will often prove quite challenging for people attempting to observe the Geminids. Many nights will be lost to cloud or fog ... and when the skies clear it will nearly always be very cold.

However, the peak observed rates of the Geminids exceed those of August's Perseids and, because Geminids are not quite as swift as Perseids, we get a better view of each one. Hence it is worth wrapping up well and braving the cold.

Peak rates from the Geminids are predicted to occur during the night of Dec 13-14 (Tue-Wed).

The Geminid radiant lies close to the star Castor (alpha Gem) and is above the horizon all night for observers in the UK, reaching its greatest altitude shortly before 02h local time.

Consequently, the general trend will be for observed Geminid numbers to be rather low at the start of the night and to then steadily increase up until the early hours of the morning and then to drop away again towards dawn. Many observers choose to start observing from around 9pm or 10pm local time.

As always, to see the most meteors, don't look directly at the radiant area. Pick an area of sky around 30 degrees from the radiant and about 50 degrees above the horizon, making sure of course that the chosen area doesn't include the Moon or obstruction by trees or buildings.

In 2016, however, there will be a serious hindrance to observing the peak of the Geminids.

Full Moon is also due to occur during the night of Dec 13-14 and, as this diagram shows, is located in nearby Taurus. When the Geminid radiant is high in the sky, the Full Moon will also be high up.

When observing visually, you obviously need to keep the bright Moon outside of your field of view.

However, doing this and meeting the 30deg/50deg guideline mentioned earlier will be virtually impossible.

Hence the best advice is to view an area of sky around 50 degrees above the horizon, but in an area of sky such that your field of view doesn't include the Moon. It will also help if you can be in the shade of a tree of building, so as to minimise the glaring from moonlight reflected from nearby surfaces.

So, if the sky is clear, wrap up well, choose a good area of the sky and you should see some nice Geminids - but be aware that with the sky background being bright, observed Geminid rates will be well below what you would see in moon-free years. (You certainly won't see the "up to 120 meteors per hour" promised by some over-excitable authors - you don't actually see that many in moon-free years!)

You can read more about the Geminids  here


Added by: Tracie Heywood