Welcome to the December night sky. This month has the longest and darkest nights of the year in the northern hemisphere.
December is also a good month for meteor showers. For example, on the 10th, we have two simultaneous showers, the Monocerotids and Chi Orionids. These are minor showers and occur close to the full Moon time, so the sky will be too bright to see any faint meteors.
On the 11th, we have the Sigma Hydrids and, on the night of the 13th until the morning of 14th, we have December’s best shower called the Geminids. This shower can produce up to 60 bright-white meteors per hour and, unusually, these meteors are in fact dust leftover from an asteroid or minor planet, not the dust from the tail of a comet.
On the 16th we have the Piscids, on the 20th the Delta Arietids and on the 22nd the Ursids.
Curiously, on the same night of the Geminids, we also have a recently discovered shower called the Leo Minorids. This shower originates from a small constellation obviously called Leo Minor.
December is, of course, the month of the winter Solstice when the Sun will be at its lowest point in the daytime sky. This year it will be on the 20th.
Last month over in the east during the evenings, the red planet Mars was steadily getting brighter and rising higher in the night sky. On December 8, Mars reaches its opposition point when it will rise at night fall and will be at its highest in the south at local midnight and will set in the west at daybreak.
Due to the eccentric orbit of Mars, the red planet will be closest to Earth on December 1, when it will be just over 80 million kilometres away and, through a telescope, the disk of Mars will appear at his largest, but it will still only be half of a percent of the width of the full Moon.
Interestingly, on this opposition night, Mars and the full Moon will be very close in fact from Portugal. The full Moon will be seen to occult or pass in front of Mars. This will happen at about 5.30am local time when the Moon will be seen over in the west-northwest at an altitude of about 24 degrees.
The Moon is full on the 8th, last quarter on the 16th, new on the 23rd and first quarter on December 30.
By Clive Jackson
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Clive Jackson is the director of the Camera Obscura – Tavira EYE attraction, located near the Castle of Tavira. Specialising in education and public outreach.
281 322 527 | [email protected] www.torredetavira.com
To see the December Sky Map click on the pdf link below
