Night sky highlights - December 2017

ROG Opening Times

Important Notice for the 31 December: The Royal Observatory North (Flamsteed House) and Meridian Line will open to the public at the later time of 11:30. The Astronomy Centre and Planetarium will open as normal at 10:00.

This month, have a look for the Geminids meteor shower and catch the last supermoon of 2017 

(Details given are for London and may vary for other parts of the UK)

Top three things to see this month

3rd Dec – Catch the last supermoon of 2017 beside the red giant star Aldebaran.

13th / 14th Dec – Spot meteors at the peak of the Geminid meteor shower.

13th – 15th Dec – Look for the Moon passing Mars and Jupiter.

Look Up! Podcast

As well as taking you through what to see in the night sky each month, Royal Observatory Greenwich astronomers pick their favourite astro news story. For December, they’re chatting about how the first evidence for exoplanets actually came about 100 years ago and a ‘zombie’ star – one that has exploded, survived and gone on to explode again.

3 December

full moon and Aldebaran

Look for the full moon close to red giant star Aldebaran. This will be the last supermoon of 2017. Spot Aldebaran (also known as the eye of Taurus) in the early evening looking towards the east. If Aldebaran was the star at the centre of our Solar System, its surface would extend out to roughly the orbit of Mercury!=

What is a supermoon?

4 December

the Moon and Betelgeuse

As we head further into winter – the constellation of Orion begins to dominate the sky – try looking for the three stars in the belt. If you follow the belt down towards the horizon, you’ll pass the brightest star in our night sky – Sirius. There are also two very bright stars on either side of the belt of Orion. Below the belt is the blue-white star called Rigel and further up you’ll find the red giant star Betelgeuse which astronomers believe is due to go supernova very soon. Look towards the south where this constellation will be higher up in the sky around midnight and on the night of 4th December spot the Moon close to Betelgeuse.

13/14 December

One of the best annual meteor showers peaks this month – the Geminids. They’ll be visible from about 4th-16th December but will reach their maximum rate on the night of 13th and early morning of 14th December. The peak rate could be as high as 100 meteors per hour as it has been in previous years, but remember if you’re looking from light polluted skies, the rate will be much less. The Moon will be in its waning crescent phase and will rise very late in the night so there’s a good chance of spotting fainter meteors too. Meteor showers are generally caused by the Earth ploughing into debris left by comets as they orbit the Sun - this material burns brightly as it falls through our atmosphere. However, the meteors of the Geminids are not caused by a comet but rather an asteroid known as 3200 Phaethon.

13-15 December

the Moon, Mars and Jupiter

If you’re an early riser then you could catch the Moon passing Mars in the constellation of Virgo and Jupiter in the constellation of Libra between 13th-15th December. Look to the east an hour before the Sun rises – these planets are bright enough to be seen with just your eyes and look like very bright stars.

18 December

The Moon reaches its new moon phase – around this phase is a great time to look for fainter objects which might normally be drowned out by moonlight. You could try searching for the Orion nebula in Orion and the Crab Nebula in Taurus. Both are vast regions of gas and dust in space but the Orion nebula is a star forming region whereas the Crab Nebula is a supernova remnant – the leftovers of a star that has ended its life.

21 December

The winter solstice falls on this day. This is when the north pole is tilted furthest away from the Sun and marks the first day of astronomical winter. This is the shortest day of the year for us (least daylight hours) and at noon the Sun will appear at its lowest position in the sky compared to any other day in the year.

26 December

first quarter moon

The Moon will reach first quarter on Boxing Day. This is a good opportunity to spot craters on the Moon. With a pair of binoculars or a telescope, look towards the terminator (the boundary between the light and dark sides of the Moon) where the shadows of the crater walls make them easier to see. It will reach its highest position in the south at around 6:00pm.

How to photograph the Moon

The Moon

Blue tycho © László Francsics
Blue tycho © László Francsics


  • 3 Dec - full moon (3:47pm)
  • 10 Dec – last quarter moon (7:51am)
  • 18 Dec – new moon (6:30am)
  • 26 Dec – first quarter moon (9:20am)

See the other amazing photographs from this year's Insight Astronomy Photographer of the Year competition in our free exhibition such as Blue Tycho by Laszlo Francsics which was the Winner for our Moon category

Stargazing tips

  • When looking at faint objects such as stars, nebulae, the Milky Way and other galaxies it is important to allow your eyes to adapt to the dark – so that you achieve night vision.
  • Allow 15 minutes for your eyes to become sensitive in the dark and remember not to look at your mobile phone or any other bright device when stargazing.
  • If you are using a star app on your phone switch on the red night vision mode.
  • Need a stargazing telescope or decent binoculars? Check out our range of high-quality observing equipment recommended by Royal Observatory astronomers:

See our range of observing equipment

Share your astronomy pictures

Congratulations to Mark McNeill for his magical photo taken in the Lake District. He shared this image on our Astrophotography Facebook page and we chose it for December's banner image.

If you want to be in with a chance to showcase your astrophotography skills on the banner for next month's night sky blog, share your photos via our Royal Observatory Astrophotography Facebook group

You can also connect with us on Twitter @ROGAstronomers

Insight Astronomy Photographer of the Year

The Cone Nebula (NGC2264) by Jason Green
The Cone Nebula (NGC2264) by Jason Green

Come and see this year’s amazing entries and winner to the world’s biggest astrophotography competition in our free exhibition at the Royal Observatory.

See the Insight Astronomy Photographer of the Year Competition

See more of the night sky 

Come on an amazing tour of this month’s night sky in our Sky Tonight live planetarium show with a festive twist during December.

See the Sky Tonight planetarium show

Central image: Devoke Water, Lake District © Mark McNeill