Caoimhín's Content

In todays piece we will be looking at the sky for Culture Night. Culture Night is the 20th of September, the day after the day this piece will have gone up on this website. Just in case you are getting to this article a few days later, most of the details presented here will remain the same.

To begin with we’re going to look at the sky from the city. I always assume that most people will be watching the sky from the city, but especially on Culture Night I know that the chances are slightly better that people are going to visit the countryside and be out under dark skies. I will still go through what we can see from the city before we go to the dark skies. Beginning with a good level of darkness as early as 8 o’clock at night, you can see the Summer Triangle is almost directly over head already, high to the South. If something is at its highest this early in the night, it won’t remain in the sky for for the entire rest of night. Similar to a Half Moon, the First Quarter Moon in particular, this triangle will begin falling below the horizon over in the West about halfway through the night.

Right in the middle of the Summer Triangle is Albireo, a particularly nice target if you have a telescope or a big enough binoculars. Albireo is one of the easiest double stars to resolve. With the naked eye, it will always look like one star, but with enough magnification you can see the two stars as two separate stars. Thanks to the two stars being different colours, even if you cant fully resolve them, you may notice the bulging shape and different colour on each side. This is easier with a telescope and harder to see with binoculars. With a big enough binoculars, two different colours should be visible at least, but with a smaller binoculars it may still appear to be a single star. Using the example of a Celestron C8, a telescope with an aperture of about 8 inches, it’s certainly resolved clearly enough to show that there are two stars rather than just one star, especially with some good eyepieces to help. I have written about Albireo in other pieces on this website, but it is always nice to look at a double star when there’s a good one in the sky. Of course we also have the planet Saturn, although it is still pretty low to the East early in the evening. The planet Saturn will be with us until the end of the month and well into October. Saturn will remain visible even into November, though it will be visible for less and less time as we go forward.

Turning around to the North we have the Plough as always, which we can follow up to the North Star. Continuing through to the other side of the North Star we will come to the W shape of Cassiopeia. There are a lot of famous things up in the sky on Culture Night, which of course includes these constellations which are always visible from the Northern Hemisphere.

On Culture Night the Moon will be close to full, but but not entirely full. If you are a regular reader of these articles then you may already know what I am about to say. The Moon of course looks great when it’s full, but when it is less than full, you can see the craters on its surface much more clearly. The shadows of the craters along the terminator, the boundary between day and night, makes them much easier to see. Seeing the true surface of the Moon let’s us see how rough that surface is. The Moon is still full enough for the Sea of Tranquility to be visible. This is of course the place where the astronauts landed in 1969, the first people to ever walk on the Moon.

Continuing to morning time, still with the light pollution of the city, there is even more to see. There are a couple of planets, along with loads of stars of course. Coming up towards the morning at this time of the year, even just a little after midnight, is the V-shape of the Hyades along with a couple of the Sisters in the Seven Sisters. Only a few of the Seven Sisters, or the Pleiades, are ever visible from the city, even when they aren’t as close to the Moon as they will be on the 20th this year. Soon after these clusters of stars, the planets Jupiter and Mars will rise into the sky. We will need to push much closer to sunrise because there is another planet to come. The smallest planet, not a dwarf planet, but the smallest true planet, Mercury, will be coming up right before the Sun. I don’t know if we will quite be able to see Mercury from the city. Using the Stellarium software, I can’t see the actual dot of Mercury, just the label for its name. It is a very small planet and very close to the glow of sunrise at the moment, making it very hard to see if you are in the city.

Thankfully, there are brighter objects, and even with the Sun coming up, Jupiter is still visible. Being brighter than any of the stars in the sky, Jupiter will remain visible after they all disappear. If you are out early enough in the morning you may be able to see the red dot of Mars as well. Brighter than Mars but fainter than Jupiter is Sirius, the brightest star. It’s very easy to make a comparison between Sirius and Jupiter at this time of the year, as they are both up at the same time, and reasonably close enough together. Jupiter will never be right next to Sirius in the sky. Jupiter, like all the other planets, must follow the ecliptic and that line across the sky is a lot higher in the sky than Sirius. Right now, Jupiter is almost directly above Sirius in the morning, making them about as close as they can get.

The view in the morning may be the nicest view at this time of the year. If you are out for Culture Night, it may be worth staying out until Culture Morning to see that little bit more. Just before pushing out to the view from the countryside, we can also see Orion in the morning. Orion is also known as An Bodach in Irish, or Daithí Bán in some parts of Connacht. Orion is one of the most famous constellations and is mostly visible from the city. Just under the Seven Sisters is the planet Uranus and way over on the other side of the sky by Saturn is the planet Neptune. It is very very hard to see Mercury full stop. Even if you are in the countryside it is hard see Mercury, but it is still harder in a city thanks to the light pollution. Unlike earlier int he month, we won’t be able to see Mercury and the planet Saturn in the sky at the same time on the morning of the 21st, but Mercury is still there at sunrise.

If you are out in the countryside without any light pollution, you will have a better chance to see Mercury and of course much more as well. Leo the Lion is also a little clearer in the countryside as well. Without light pollution, even with some sunrise glow, it’s a little easier to see the fainter stars that make up the outline of Leo. Staying in the countryside and moving earlier in the night, still a little after midnight, brings Saturn back into the sky. This lets us see Mars, Jupiter and Saturn, as well as Uranus if your eyes are very good. Uranus is tough to see with the naked eye even under perfect conditions, but on Culture Night you also have to deal with the Moon. The light of the Moon will interfere with your view of faint objects, and it is rather close to Uranus in the sky as well. If you keep the Moon of out of your field of view that will help a bit, as will a cover or blinder for your telescope, something to stop the light of the Moon from falling directly on the lens or opening of your telescope. A darker sky makes everything look better and that includes the Hyades. Besides Aldebaran, many of the Hyades have names like Secunda Hyadum, the Second of the Hyades, and Prima Hyadum, the First of the Hyades. Prima Hyadum is the point of the V shape. The Seven Sisters will look much better without light pollution, especially if you are limited to the naked eye.

If you do have a binoculars or a small telescope, the Seven Sisters are one of the best things to look at no matter where you are. You can get a great view of the Pleiades just a good binoculars. Trying to look at Uranus with the same magnification reveals no visible details at all. Uranus is just too far from us for much to be seen, especially with just binoculars. Taking a look at the Hyades under magnification, there isn’t much nebulosity or “cloudiness”, the kind we can see when we look at the Pleiades. The Seven Sisters still have a nebula associated with them, but there isn’t much of that when we are looking at the Hyades. A lot more nebulosity is visible if you look into Orion, or An Bodach, especially Orion’s Sword. Orion’s Belt is one of the most famous locations in the sky, but Orion’s Sword is just below it and in my opinion the Sword should be more famous. Through a telescope or binoculars, an awesome nebula is revealed. In particular it is a stellar nursery, a place where new stars form.

At the bottom of Orion, just outside the bright star Rigel, is another, more diffuse, nebula. I’m going to talk more about this particular nebula when we are closer to Halloween. Through a good telescope of binoculars, the glowing nebula seems to outline a shape, the face of a witch. It looks a bit like the classic cartoon witch in side profile, with a big nose and pointy or warty chin. It is almost like a caricature of a cartoon witch, but it gives its name to the Witch Head Nebula. There are a few nebulae up in space with sort of “spooky” names, something I will get back to later in October.

That is all in the sky in the morning, the morning after Culture Night, though if you are out the morning of Culture Night then things will look mostly the same. If you are out in the countryside without any light pollution earlier in the evening, the sky will still look much better than it would in the city. Coming back to around, 8:30 in the evening, this keeps us early but comfortably after sunset. Too close to sunset there may be too much light from the Sun for the Milky Way to be visible, especially with the light of the Moon included. Once all of the Sun’s light has left the sky, even with the Moon in the sky, the glow of the Milky way should just about shine through. Even as early as 8:30, you may be able to catch the Pleiades just a bit lower and further East than the Moon, at least if you are out in the countryside.

Without any light pollution you should be able to see the Milky Way even with the Moon in the sky on Culture Night. However, if you are remaining in the countryside for the whole weekend, it’s worth taking a look a couple of days after Culture Night. By then, the Moon will not be in the sky when the Sun goes down and the Milky Way should be a lot easier to see. The light of the Moon certainly interferes with our ability to see fainter objects in the sky, like the Andromeda Galaxy. On the other hand, dark skies are dark because there is a lack of unnatural lights, the lights that people create, like street lights. Without those lights, it can be nice to get a little light from the Moon, so you can see where you’re walking so you don’t walk into anything.

The Andromeda Galaxy is visible to the naked eye under good conditions, though it will be obscured a little by the light of the Moon. With a binoculars or telescope it should certainly come into view, even from the city. It is a collection of over a trillion stars and is the furthest thing from us that you can see with your naked eye. The Andromeda Galaxy is just over 2 and a half million light years, over 778 kiloparsecs. Those are just two different measurements of distance, like a mile versus a kilometer. A kiloparsec is much bigger than a lightyear. If we are talking about things that are in our own galaxy with us, inside the Milky Way, a lightyear is almost always big enough. When we are measuring the distance to something much further from us, like another galaxy, sometimes we have to use kiloparsecs to keep the numbers manageable. The Andromeda Galaxy will be up to be seen as early as 8:30 on Culture Night.

I hope you enjoyed this quick run through of what will be visible on Culture Night this year, and I’m sure that you will get a kick out of anything you attend in person for Culture Night as well. If you enjoyed this article then please do like it, and if you enjoy this kind of content you can subscribe to this website and my YouTube channel to get more. Hopefully you’ll come back here after Culture Night for the next article.