The Night Sky in December: The Planet-Packed Sky

25 Nov

Written By Neil, Science and Environment Writer

Take five minutes out of your day from your desk and see if you can solve this simple puzzle: go to where you can see the most ancient thing. No, I am not talking about going to your museum to uncover a dusty fossil (sorry archaeologists!) or some old artefact. With some consideration, you will find your answer to be outside the window – up the starry sky where the oldest thing we can see is the sky with its stars, billions of years old.

As the COVID-19 pandemic continues to haunt us, we are once again restricted by the distances we can travel and the journeys we can embark upon. Our brains are restricted in their imagination, their dreams and their ability to wonder; to wonder what lies beyond our eyes can see. However, you can still ‘travel’ far distances, to unique worlds hundreds of lightyears away! No telescopes or special equipment is needed – a series of exciting adventures await you every day directly above your head, and unlike most great ventures, they require no hard work or dedication.

The Planet-Packed Sky: Mars

Reddish Mars at its peak in the South

On 13 October 2020, Mars was at opposition, meaning that it was at its closest to Earth, which will not take place for another fifteen years.

Though now speeding away from it, the red planet still offers a great opportunity for space enthusiasts to explore. Upon sunset, the planet will unveil itself around the East to South-Eastern sky, moving to peak in the South between 18:45 and 20:15 hours, travelling westwards through late evening and midnight until setting in the West at 01:30 hours.

The planet’s orange hue is unmissable to the naked eye, and the average binoculars will allow one to see the planet as a small circle. Mars, known as the red planet, is a great place for anyone to start sky watching since it is practically impossible to miss.

The BBC Symphony Orchestra’s performance of Holst’s ‘Mars, the Bringer of War’ from his suite The Planets will put you in the mood for some stargazing!

The Planet-Packed Sky: Jupiter and Saturn

Bright Jupiter and Saturn seen in the South-West with a waxing crescent moon.

Still very simple to observe, planets Jupiter and Saturn never fail to impress. They are the largest planets in the Solar System, and can be seen together in one view throughout the month, Jupiter being the brightest.

On 21 December 2020, the gas giants will be in the Great Conjunction. This is a rare event, taking place once every twenty years. The planets will appear so close together that they will look like a large, luminous double-planet pair: unmissable to anyone who sets their eyes in the right direction.

Throughout December, Jupiter and Saturn can be seen together moving from around the South to South-West, Saturn just to the upper left of Jupiter before the Conjunction, and Jupiter above to the left of Saturn afterwards.

Unlike Mars, there is a shorter window of time in which these planets can be seen every evening: that is between sunset and around 18:30 hours in early December and up to 17:45 hours on the day of the Great Conjunction.

Observe them every day, and you will notice that they appear to get closer to each other until 21 December, then begin to separate again. Many astronomers describe them as friends who eventually ‘fall out‘, but then make up again every twenty years! If this is not enough to excite you, then get out your binoculars – if you hold them still enough, you may see the ring faintly around Saturn and the biggest of Jupiter’s seventy-nine moons next to it, Ganymede! This planetary pair excites astronomers all over the world!

The Planet-Packed Sky: Mercury and Venus

Venus as seen in the South-East before sunrise

Another pair of planets reveal themselves in the morning: these are Mercury and Venus.

In the South-East, dim Mercury rises at around 07:00 hours, far to the lower left of Venus. However, the planet is only visible in the very early days of December making it considered a great challenge even for the most seasoned of sky watchers.

Venus, however, is much easier to find. In early December, look for the planet around the South-East earliest from 05:30 hours until sunrise. In mid-December, the planet will take on the skies earliest between 06:15 and sunrise and in late December, between around 06:45 and sunrise.

The planet is best viewed earlier in the month due to the larger time window, and also should be viewed halfway between its rise and sunrise to allow it time to stand high into the southeast, yet still not be obscured by twilight. Regardless, the white-sliver planet is great for those who ‘rise’ earlier in the morning.

The Meteor Showers

The sky is truly planet-packed this month, but the fun does not stop there! Meteor showers are debris entering the Earth’s atmosphere and burning up as they descend. These create what some people call ‘shooting stars’.

The first of two meteor showers this month is the Geminids, from the asteroid 3200 Phaethon. This shower, falling this year on the nights of 13 and 14 December, is known for being the ‘best shower in the heavens’.

From Dartford, the most meteors will be visible at around 02:00 hours: potentially 120 meteors per hour originating from the constellation Gemini, under ideal conditions. Even a novice is bound to see at least one sprinting through the skies!

The second is the Ursids meteor shower, left behind by the comet 8P/Tuttle. This is a great shower for more experienced watchers, producing up to ten meteors per hour on the nights of 21 and 22 December.

Unlike planets and stars, meteor showers do not stay steady for one to view them. Instead, they will sprint across the sky at different times throughout the night. To get the most out of them, lie somewhere outside with little light, allow your eyes to adjust to complete darkness and keep your eyes on the skies! The longer you ‘camp’ for, the better!

This is just a glimpse of what this month has to offer: there are many more astronomical events taking place this month, including a full moon to end it. The brightest stars and events such as the December Solstice and the solar eclipse in some parts of the world have not even been touched upon.

If you are interested in finding out more about these events or looking for date-specific guidance on where to find the planets or showers, the free app ‘Sky Safari’ for iOS and Android allows you to point at a sky object and verify what it is, as well as guided written and audio tours. The app ‘Sky Guide’ is also very helpful. Websites such as www.timeanddate.com also help in astronomy planning. The following table summarises all of the information in this article:

What?	Where?	When?
Mercury	Low in the south-east.	Just before/during sunrise in early December.
Venus	The south-east (higher moving southward towards sunrise).	Up to two hours until sunset- the later in the month observed, the less time before sunset that it is visible.
Mars	Travelling from south-east to west through the night	Sunset to around 01:30 hours.
Jupiter and Saturn	South-west to west.	Sunset to around 18:30 hours. 21st December: The Great Conjunction (sunset to around 17:45 hours).
Geminids meteor shower	Meteors will originate from the constellation Gemini, but can appear anywhere in the sky.	Peak of activity on 13 and 14 December. Most meteors at around 02:00 hours but can be seen at any time.
Ursids meteor shower	Meteors will originate from 63°N, but can appear anywhere in the sky.	Peak of activity on 21 and 22 December.

Sky watching is a great hobby, especially at a difficult time like this – allowing you to connect with someone else, perhaps a family member living on another continent, knowing that you are both gazing as some of nature’s ancient and most beautiful celestial creations.

We would love to hear about your experience stargazing – please do share your discoveries with us through our Twitter @dgsjournalism

Neil, Science and Environment Writer