As it’s December, the month of the Winter Solstice, we have our Shortest Day with under 7 hours of daylight, so you don’t have to be out late to go stargazing. Although most of the bright stars are missing from our sky this month, it is a good time to spot the Andromeda Galaxy and also three bright planets, Venus, Saturn and Jupiter, which line up in the southern sky as darkness falls. We also have the best meteor shower of the year, the Geminids, which peaks on the night of 13-14 December it may be possible to see up to 120 meteors an hour in the few hours before sunrise on 14 December. The ConstellationsThis month, the sun sets around 4:00 pm and the stars and the constellations start to become visible from about 6:00 pm onwards. As with November, there is a great signpost, in the form of the Square of Pegasus, to help you find your way around the sky. It is a huge square made up of four stars of nearly equal brightness: Scheat, Alpheratz, Markab and Algenib and, in the early evening, you should be able to see it high up in the south, above and to the left of Jupiter, which will be sitting in the south-west. The top left star of the Square is Alpheratz. It is the brightest star in the constellation of Andromeda, which is marked by a line of three more stars running up and to the left of it. You can use this line to find the Andromeda Galaxy, one of the most famous features of the night sky and the nearest spiral galaxy to our own, the Milky Way. The best way to find it is to start Alpheratz and go a further two stars along the line, turn right and count another two faint stars along, and the Andromeda Galaxy (M31) will be close to the second faint star. If you are in a town, you’ll probably need a pair of binoculars to spot it, but if you’re in a dark place out in the country, you should be able to pick it out without using binoculars.
There will be more about Taurus and Orion next month, but for the moment, draw a line using the three stars in Orion's belt and follow it through Aldebaran and you’ll find the Pleiades star cluster (M45) a bit beyond it. This cluster is the brightest open constellation we can see in the night sky and is a grouping of stars, seven of which are visible to the naked eye, but the entire constellation has more than 1,400 stars. The name comes from the early Greeks who referred to the constellation as the Pleiades, or the Seven Sisters, who were daughters of Atlas and Pleione. These stars are mentioned three times in the Bible and are linked to origin stories for many American Indian tribes. If you look north, you’ll see the same stars as you would in any other month, but their orientation varies from month to month. In December the familiar Plough asterism, which many people recognise, is moving from the north to the north-east. If you follow its two right-hand stars upward, veer a little bit to the right and you’ll find Polaris, the Pole Star. If you look high up over to the north-east, you can see Castor and Pollux, the two brightest stars in the Constellation of Gemini (the Twins), which represent the heads of The Twins. Meanwhile, low down in the North-West, you will find Vega, the brightest star in the Constellation of Lyra (the Lyre). It is the fifth-brightest star in the night sky, and the second-brightest star in the northern celestial hemisphere after Arcturus. The MoonAt the very start of the month, we are close to a new Moon (no Moon) as this occurs on 4 December and if it’s clear a couple of nights later, on 6 December, you will find the slightest of crescent Moons below and to the right of a bright shining Venus as it sets in the south-west at around 5:30 pm. On the following evening of 7 December, the crescent moon will to the left of Venus and will set about an hour later at around 6:30 pm. At sundown on 8 December the moon will be found directly south, hanging in-between Venus and Jupiter, while on 9 December, it will have moved to the left of Jupiter.
On 20 December, the moon will be 98.5% full and will rise a little further to the north at just after 4:30 pm to spend the night traversing the sky between the twins of Gemini, which you can find by spotting the constellation’s brightest stars, Castor and Pollux above and to the left of it. Three nights later, on 23 December, you will find the moon close to Regulus, the brightest star in the constellation of Leo. The first quarter moon is on 27 December and on 28 December, you will see it lying very close Spica once it has risen at just after 1:30 am. This month’s full Moon is called the Cold Moon because December is the first month of winter. Its Old English/Anglo-Saxon name is the Moon Before Yule, while another name is Wolf Moon, however, this is more commonly used for January’s Full Moon. The PlanetsIf you watch the sky in the south-west this month as darkness falls, you will see a diagonal line of three bright planets. Venus will be to the right, Saturn in the middle and Jupiter to the left. As first half of the month progresses, you will notice Venus moving closer to the other two, but just after half-way through the month it will change direction and move back the other way, heading right and downwards. Venus will get brighter and brighter until 7 December, the day on which it reaches its brightest during its appearance in our 2021 evening sky. It will then begin to fade and if you look at it through a telescope, you will be able to see Venus shrink dramatically to a narrow crescent as the month passes. At the start of the month, it sets at 6:30 pm and by the end of the month it drops below the horizon at 5:20 pm. If you do look for it towards the end of the month, you may be able to see Mercury sitting beneath it and moving from its right to its left as each night passes. Above and to the left of Venus, you will find Saturn, a gas giant that is the sixth planet from the Sun and the second largest in our Solar System. Then, if you look further left and up a little, you will see Jupiter, another gas giant that is the fifth planet from the Sun and the largest our Solar System. Saturn sets in the south-west at around 7:30 pm and Jupiter sets at about 9:30 pm. If you use binoculars or a telescope you will be able to see Jupiter’s four bright moons and Saturn’s rings. 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 11:30 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 4:30 am, over to the east about halfway between the constellations of Aries and Taurus. Finally, Mars begins to make an appearance this month and you will find it low in the morning twilight as it rises in the south-east at around 7:00 am. Meteor ShowersDecember is the month for viewing the shooting stars of the Geminids Meteor Shower, which unusually are not debris from a comet, but rather debris from an asteroid called Phaethon. The Geminids have become more plentiful in recent years and are considered by many to be the best meteor shower of the year. They are active from 4-17 December and during their peak, which this year is on the night of 13-14 December, it can be possible to see around 120 meteors per hour. Their radiant point is in the Constellation of Gemini (The Twins) and this year it is close to one of its two bright stars, Castor, over in the north-east sky. Although this is where they originate from, you’ll be able to see them at any point across the sky while they burn up in the upper atmosphere, some 60 miles (100 km) above Earth’s surface. They become visible when the radiant point is high up in the sky and it will get there by about 10:00 pm, so begin looking for them from then. However, the best time is normally at about 2:00 am, when the radiant point is at its highest in the sky, but this year, a waxing gibbous moon will be in the sky until about 3:30 am and will drown out the fainter meteors. It will therefore be best to wait until after the moon has set and look for them in the 2-3 hours of complete darkness between then and before sunrise on the morning of 14 December. Winter SolsticeThis year, the Winter Solstice will occur on 21 December at 3:59 pm am and is the exact moment when the northern hemisphere is tilted furthest away from the Sun. However, many people refer to the Winter Solstice as the Shortest Day of the year, when the number of hours of daylight are at their minimum and the number of hours of night are at their maximum. On 21 December this year, our sunrise will be 8:55 am and our sunset will be 3:47 pm, giving us 6 hours and 52 minutes of daylight.
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As we move away from the Autumn Equinox and towards the Winter Solstice it seems to me that, along with the days getting shorter and colder, the evening skies are getting brighter and bolder. We often get brooding skies, with the oranges, pinks and reds from the setting sun breaking up the greys, blues and purples of clearing storm clouds to produce dramatic scenes such as one I witnessed at Castle Tioram on a late-November afternoon and shown the image below. This makes me beg the question: Are late autumn and winter sunsets better than those we get at other times of the year? Well, it turns out that scientific studies have confirmed this to be the case and they have discovered the reasons why Scientific researchers have found that the peak sunset season is from November through to February and that this is down to a combination three things. These are the type and quantity of the cloud cover, cooler air temperatures and how the Earth is tilted towards the sun at this time of the year. Contrary to what you might think, we need clouds for a good sunset and they have to be the right kind of clouds. If they are too low down on the horizon, they will block out the Sun’s rays and prevent a sunset. Instead, we need mid to high level clouds that will refract the sunlight and give us those beautiful sunset colours. This happens more in autumn and winter because the weather patterns we get then tend to bring mid and high-level altocumulus, altostratus and cirrus clouds. The cooler temperatures mean that the air is less humid and that there is less water vapour to capture dust particles that are in the air and create the haze which is often a feature of the summer months. When present, this haze scatters sunlight and reduces its intensity. So, in autumn and winter, the lower humidity means that the air is clearer and we see the colours produced by the setting sun in all their intensity. Finally, as we approach the winter solstice, the North Pole gets tilted further away from the sun, lengthening the time taken for the sun to set. This, in turn, means that the sunset colours last longer than at the equinoxes, for example, when the sun sinks very quickly towards the horizon at a 90-degree angle. The result is that we have more time to enjoy the sunset colours and the sunset colours have more time to make an impact on us. Despite all of these variables, predicting sunsets doesn’t have to be hard. All you need to do is keep an eye out for the following key indicators:
Mid to high-level clouds (2km and above) Cloud coverage - 30 to 70 percent Humidity - low but not too low Clean air Prior rainfall - no less than 2 to 6 hours before Wind speed - low or non-existent There are many online forecasts for these weather conditions and the one I refer to most is windy.com. So why don’t you have a go at predicting a sunset and head west at what you think might be a good time. You never know, you may be well rewarded for your efforts! The clocks have changed and the sun now sets at around 4:00 pm to give us long dark nights for stargazing. The Summer Triangle, which we have been using for navigation is disappearing from view, but the Great Square of Pegasus is now in the southern sky for us instead to find the constellations that lie around it, many of which have names with watery connections. Many of the planets are visible to the naked eye, with Venus shining particularly bright because it reached its furthest point from the Sun on 29 October. Finally, you may be able to spot shooting stars produced as a steady stream from the Taurid meteor showers in the first part of the month, while there is also the possibility of spotting some from the Leonids meteor shower which peaks on the morning of November 17. The ConstellationsFollowing the clock change at end of October, the sun now sets at around 4:00 pm, meaning that the stars and constellations start to become visible from about 17:30 pm onwards. During the previous three months we have been watching the Milky Way get lower and lower in the southern night sky and you may have noticed the constellations in the south getting dimmer. This is because the position of the Earth is now such that we are looking out of the plane of our galaxy and into the rest of the universe. However, the Milky Way has not gone altogether, and you can see it over in the west along with the Summer Triangle of the three bright stars of Vega, Altair and Deneb, which we have been using to navigate our way around the night sky in previous months.
The constellation of Pegasus represents the Flying Horse of Greek mythology and the Square marks the horse’s body. You may find it difficult to make out the horse because it is upside down and the constellation represents only the top half of its body and its head. However, you may be able to pick out Enif, the constellation’s brightest star which is below and to the right of the Square and Altair. Enif is an orange supergiant star that is 5,000 times brighter than the Sun and it represents the horse’s nose. If you follow the diagonal down from the top left of the Square to beyond its bottom right star, you’ll come to a faint group of stars known as the Water Jar of Aquarius. It is an asterism formed by four relatively bright stars in the constellation of Aquarius (the Water-Carrier). It is easily recognised by its arrow shape, which looks a bit like a fighter plane with swept wings. Though it’s not the brightest part of Aquarius, it’s a good pattern that helps you to find its other stars. From the top left edge of the Square stretches a line of stars in the constellation of Andromeda, which is named after Andromeda, daughter of Cassiopeia, in the Greek myth, who was chained to a rock to be eaten by the sea monster Cetus. It is the home of the Andromeda Galaxy which, at approximately 2.5 million light-years from Earth, is the nearest spiral galaxy to our own galaxy, the Milky Way. It is also the most distant object that you are likely to see without an optical aid but if you can’t find it with the naked eye, then use binoculars through and look for a little oval blur. Below Andromeda and to the left of Pegasus is where you will find the constellation of Pisces (the Fishes). It is very faint and difficult to see, so the best way to find it is to look directly below the Square of Pegasus for the Circlet of Pisces, which is a pentagonal asterism of 5 stars that marks the head of the Western Fish. Once you’ve found the it, go on from there to catch the Eastern Fish that’s jumping upward to the east of the Square of Pegasus. The entire constellation looks like the letter V. Below Pisces is the constellation of Cetus, the Sea Monster which in Greek mythology both Perseus and Heracles needed to slay. You’ll find its tail marked by a fairly bright star called Diphda located low down in the sky, almost directly below the left-hand edge of the Square of Pegasus, while further over to the left and up a little, you’ll find Menkar, a reasonably bright star that marks its head. You may have noticed that all the constellations in this part of the sky have watery connections. It is said that this is because the Sun travelled through these constellations during the wet season in ancient Mesopotamia, which was from November to March, and flooding was a major problem. Many of our constellations date from that location and time. Finally, to the east of the Square is Aries, the Ram, whose three main stars form an easily recognised triangle, and another more regular triangle, actually called Tringulum, the Triangle, which contains the nearby galaxy M33. This will be visible with binoculars if you have a reasonably dark sky. If you look north, you’ll see the same stars as you would in any other month, except that their orientation varies. This month the familiar Plough asterism, which many people will recognise, is low down in the north at the moment with its rectangular end almost directly below Polaris, the Pole Star. If you look over to the north-east you can see Capella. It is a yellow giant star, the brightest star in the constellation of Auriga (the Charioteer), the sixth-brightest star in the night sky, and the third-brightest in the northern celestial hemisphere after Arcturus and Vega. The MoonAt the very start of the month, we are close to a new Moon (no Moon) as this occurs on 4 November and if it’s clear a couple of nights later, on 6 November, you will find the slightest of crescent Moons setting in the south west at around 4:30 pm. However, it may be difficult to see the Moon on that evening as it will be lying close to where the sun has set. You'll probably find it easier to see it on the following evenings of 7 November and 8 November as it will have moved slightly to the left and will be sitting further from the sun. It will also be next to a bright shining Venus on these two evenings. The first quarter Moon (a half moon) is on 11 November, and it will be sitting beneath Jupiter, low down on the southern horizon.
There is a partial eclipse of the Moon on 19 November, but it takes place just before sunrise, when the Moon will be low down in the north-west. This means that will need to be quite far west and north in the UK to see anything of it. If you are, then you may see the dark part of the Earth’s shadow starting to move onto the Moon at 7:18 am. This month’s full Moon is called the Beaver Moon and there is disagreement over the origin this name. Some say it comes from Native Americans setting beaver traps during this month, while others say the name comes from the heavy activity of beavers building their winter dams. It is also known as the Frosty Moon, and along with the December Full Moon some called it the Oak Moon. Traditionally, if the Beaver Moon is the last Full Moon before the winter solstice, it is also called the Mourning Moon. The PlanetsWhen it is getting dark, you may be able to spot Venus hanging low down on the western horizon just before it sets at around 5:30pm. It is shining brightly because it reached Elongation, its furthest point from the Sun, on 29 October and will take a few weeks to move away and become less bright as it does so. Well to the left of Venus, in the south, you will find Jupiter, a gas giant that is the fifth planet from the Sun and the largest our Solar System. It is the second brightest planet in our night sky at the moment and to the right of it is a fainter Saturn. Saturn, another gas giant, is the sixth planet from the Sun and the second-largest in our Solar System. Saturn sets in the south west at around 9:30 pm and Jupiter at about 11:00 pm. If you use binoculars or a telescope you will be able to see Jupiter’s four bright moons and Saturn’s rings. Neptune will be above the horizon until about 1:30 am and you will find it to the left of Jupiter in Aquarius. However, it will be very dim and therefore difficult to see, even with binoculars or a telescope. Its near twin in size, Uranus, can be found above the horizon all night long, over to the east in Aries. It reaches opposition on 5 November, when it will be at its closest to Earth this year at 1,742 million miles away. Even so, it is only just visible to the naked eye and will be difficult to distinguish from the stars. It will be better to look for it with binoculars night after night and spot it moving against the background of stars. Last month was the best month of the year to see Mercury because it reached its maximum separation (elongation) from the Sun on 25 October, so in the first part of this month you will still be able to see it in the south-east sky just before sunrise. Mars is too close to the Sun to be visible this month. Meteor ShowersDuring the first part of the month there South or North Taurid meteor showers, which unlike other meteor showers, don’t have strong peaks but instead have “staying power” and produce a steady stream of meteors over a number of weeks. The South Taurids are active from about September 10 to November 20, while the North Taurids are active from about October 20 to December 10. They both produce a steady stream of about 5 meteors/hour and because they overlap up until the 20 November, you can expect to see up to 10 meteors/hour during the first 3 weeks of the month. However, the best time to look for them will be at the start of the month, a few days either side of the new Moon on 4 November when there will be little or no moonlight to drown them out.
We also have the Leonid meteor shower this month and it is known for periodic storms of historic proportions, when shooting stars fall like rain. While no storm is predicted for the 2021 Leonids, you can still catch plenty of meteors between 6 November and 30 November. The meteor shower peaks the morning of November 17 but unfortunately, this is two days before a full moon, meaning that the Moon will hang around for most the night, brightening the sky and washing out many of the meteors. However, as the Leonid meteors can appear in huge numbers, do keep an eye out for them from about 10:30 pm, which is when the radiant point rises above the horizon. You never know, you might spot some. |
AuthorHi, I’m Steven Marshall, a Scottish landscape photographer based at Rockpool House in the heart of the beautiful West Highland Peninsulas of Sunart, Morvern, Moidart, Ardgour and Ardnamurchan. Get in touch for photography tuition, tours and print sales. Archives
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