January and the start of the year brings us a dazzling array of stars to find our way through, with Betelgeuse and Rigel blazing in Orion (the Hunter), glorious Sirius in Canis Major (the Great Dog) and the bright red Aldebaran in Taurus (the Bull). There is also Capella crowning Auriga (the Charioteer) and Castor and Pollux (the celestial Twins) in Gemini. There is also an opportunity to spot some shooting stars, with the peak of the Quadrantid meteor shower on the night of 3-4 January and as there will be little or no moonlight to spoil the show, you may see up to 100 meteors per hour at its peak.
This month, the sun sets around 4:15 pm and the stars and the constellations start to become visible from about 6:15 pm onwards. As darkness falls, the most obvious constellation you’ll see is Orion (The Hunter), with its three bright stars in a line, surrounded by a quadrilateral of other stars. You see it rising in the east not long after dark and by 10:00 pm it will be up there in the centre of the southern sky. As it is the brightest constellation in the sky, you’ll be able to see it even when there is a bright moon or some light pollution.
If you follow the line of Orion’s belt heading left and slightly down, you will find Sirius. It is in Canis Major, the Greater Dog. It is the brightest star in the night sky and appears very low down at our northern latitude. This can cause it to twinkle quite strongly, especially on a clear frosty night.
Canis Major is just one of Orion’s dogs. The other, Canis Minor or the Lesser Dog, can be found directly to his left and its main star is Procyon, the 8th brightest star in the sky. Above Procyon are two stars, Castor and Pollux, which mark the heads of the Twins, Gemini. The bodies of the Twins are the two lines of stars which extend towards Orion.
Another thing you can see in the southern sky is the Winter Circle, a pattern of stars that is not a constellation. It’s made up of a lot of separate stars, in different constellations, so it’s what is called an asterism. It doesn’t form a perfect circle, but instead a hexagon that you can find if you start at Capella and move clockwise to Aldebaran, Rigel, Sirius, Procyon, Pollux, and Castor. In addition to the Winter Circle, Orion’s bright star Betelgeuse forms an equilateral triangle with the stars Sirius and Procyon. This what is called the Winter Triangle.
If you go back to Orion’s belt and look carefully about halfway down between it and the two stars that mark the Hunter’s left and right feet, you should be able to see a bright patch. This is the Orion Nebula, one of the brightest nebulae, or clouds of gas from which stars are born in the sky. One of many in our Milky Way galaxy, it lies roughly 1,300 light-years from Earth and is some 30 to 40 light-years in diameter. Look at it with binoculars or a telescope and you should see swirls of gas, though the darker and clearer the sky you have, the better. In it, you should also be able to pick out The Trapezium Cluster, which is made up of four bright stars that are only a million or so years old, babies on the scale of star lifetimes.
Looking North, the thing to bear in mind is that the constellations you see do not change from month to month, it is only their orientation that changes. Look for the seven stars of the Plough, up in the north-east, and the W-shape of Cassiopeia, high up in the north-west at this time of year. The Plough is known as the Big Dipper in North America. Use its two right-hand stars to point towards the Pole Star, Polaris, which is always in the same position in the sky. Once you’ve found it, you can use it to get your bearings on any night, though all the other northern constellations wheel around it anticlockwise.
Polaris is a second-magnitude star, about the same as the stars in the Plough or Cassiopeia, so don’t expect anything particularly bright. It’s just by chance that this millennium it happens to be very close to the pole of the sky, but there is a slow movement of the sky over the centuries that shifts the position of the stars, and 1000 years ago it wasn’t as close as it is now.
The first quarter Moon (a half moon) is on 9 January and will be over in the south-east as darkness falls, while this month’s full Moon is on 17 January, becoming 100% full at just after 11:48 pm. This means that it will appear full on the nights of 17-18 January, 16-17 January, and 18-19 January. It will rise in the north-east just after 3:30 pm on the 17 January, just after 2:30 pm on the 16 January and just after 4:30 pm on 18 January. On the night of 17-18 January, the full Moon will spend the night traversing the sky close the twins of Gemini, which you can find by spotting the constellation’s brightest stars, Castor and Pollux almost above it. Then on the nights of the 19-20 January and 21-22 January, you will find the Moon close to Regulus, the brightest star in the constellation of Leo.
The last quarter Moon is on 25 January and on 29 January, you will see it rising in the south-east at about 7:30 am, with Mars and Venus above and to the left of it.
This month’s full Moon is called the Wolf Moon, after the howling of hungry wolves lamenting the scarcity of food in midwinter. Other names include the Moon After Yule, Old Moon, Ice Moon, and Snow Moon.
If you watch the sky in the south-west during the first few days of the New Year, you will see Venus (the Evening Star), very low down just after sunset. It will eventually disappear from the night sky when it passes between the Earth and the Sun on 9 January but will reappear over in the south-east at daybreak from about 15 January to become the Morning Star.
Mercury lies to the left of Venus at the start of the month, remaining low in the evening sky for almost two weeks. It reaches its greatest separation from the Sun on 7 January, setting just before 6:00 pm. It will remain visible until 12 January before disappearing into the glow of the sun in the days after that.
Jupiter will be above and to the left of these two planets, with Saturn in between. This gas giant, which is the fifth planet from the Sun and the largest our Solar System, will set at around 8:00 pm and if you look at it through binoculars or a telescope you should be able to see its four bright moons. Saturn is the other gas giant, the sixth planet from the Sun and the second largest in our Solar System. It will set at about 6:00 pm at the start of the month before disappearing from view in the dusk twilight during the second half of the month.
Go up and left again and you will find Neptune a little bit above the constellation of Aquarius. It will be above the horizon until about 9:30 pm, but it will be very dim and therefore difficult to see, even with binoculars or a telescope. Its near twin in size, Uranus, will be a little bit brighter and can be found above the horizon until about 2:00 am, over to the east about halfway between the constellations of Pisces and Taurus.
Finally, following on from last month, Mars continues to make its reappearance and you will find it low in the morning twilight as it rises in the south-east at around 6:00 am. It starts the month near Antares and at the end of the month, the Red Planet will lie to below and to the right of Venus in the morning sky, albeit 250 times fainter and therefore more difficult to see.
The Quadrantid meteor shower, always the year’s first meteor shower, will peak on the night of 3-4 January and with this being very close to the new Moon of 2 January, there will be little or no moonlight to spoil the show. So, if we do get a clear night on 3-4 January and you do decide to look for meteors, start looking just before 9:00 pm on 3 January as this is when the shower is expected to reach peak activity.
At its peak, the shower is expected to produce around 120 meteors per hour. However, this is a theoretical maximum so, in practice, the number of meteors you are likely to see will be lower than this but given there will be little or no moonlight this year, you can realistically expect to see up to 100 meteors per hour at the peak.
However, the best time to look will be just before dawn on 4 January as this is when the meteor shower’s radiant point is at its highest point in the sky. You’ll find it in the north sky, directly below The Plough, but do bear in mind that you don’t have to look north as the meteors will appear across all the sky.