The Hamburger Galaxy is well placed in the sky this week, while Comet C 2023 A3 Tsuchinshan-ATLAS makes an appearance amongst the stars. Find out how you can see these for yourself as well as our usual stargazing highlights in this week’s podcast guide, Star Diary, 20 to 26 May 2024.
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Chris: Hello and welcome to Star Diary, the podcast from the makers of BBC Sky at Night Magazine. You can subscribe to the digital edition of the magazine by visiting iTunes, Google Play, or Apple News, or to the print edition by visiting www.skyatnightmagazine.com.
Ezzy: Greetings listeners. And welcome to Star Diary, a weekly guide to the best things to see in the northern hemisphere's night sky. As we are based in the UK, all times are in BST. In this episode, we'll be covering the coming week from 20 to 26 May. I'm features editor Ezzy Pearson, and I'm joined on the podcast this week by Katrin Raynor.
Hello, Katrin.
Katrin: Hello, Ezzy. How are you doing?
Ezzy: I'm doing well. Do we have a lot of interesting things coming up in the night sky this week?
Listen to the previous episode, Star Diary: The Milky Way puts on a show (13 to 19 May 2024)
Katrin: We do. So, this week, however, the focus really is on the Moon, because planet wise there isn't much happening. We do have a couple of fantastic pairings between the Moon and two prominent stars, offering keen astrophotographers some wonderful opportunities to take some lovely photographs.
And I'm also going to introduce a trio of galaxies to check out. And unfortunately, Ezzy, this week it's all about staying up late or getting up very early. As we have discussed before, I don't think either of us are great at either of those. Yes, be prepared.
Ezzy: I'm fine with staying up late. Staying up late, I can keep going until 4:00 in the morning and be absolutely fine. I tend to loop around that way if it's something early.
Katrin: Yeah, it's the getting up early that can be a problem. So, whereas I think I'm the opposite, I'd rather be up early than stay up late. I do like to go to bed quite early. Terrible. So, we start the week off with a 93% lit waxing gibbous Moon. And on 20th there's going to be a lovely coupling between the Moon and Spica, the brightest star in the constellation of Virgo, the Maiden.
So if you locate the Moon in the south, and if you don't know where south is, then look for the Moon. It's going to be bright, you're going to be looking in the south. And I have mentioned before how much I enjoy, you know, seeing a bright star or planet near a full or nearly full Moon, so this is going to be something that I'm going to look forward to seeing again.
And if you step outside, say after 10pm, you will see Spica shining brightly, diagonally to the bottom left of the Moon. And as the night goes on, note the slight changing positions of the Moon and Spica. And in the morning of 21st, at around 2am, you will see Spica and the Moon close to each other, almost side by side.
Then on 23 and 24th, we do have a couple of great observing events happening in the constellation of Scorpius, the Scorpion on the night of 23rd and into 24th. So it will be worth staying up late on the 23rd to get outside to see the start of the Moon occulting a globular cluster. And then passing under a red supergiant in the early hours of 24th.
So arachnophobes, you might want to put yourself on mute. So the full Moon will begin to occult globular cluster M4 at around 12:45AM on the morning of 24th. So M4, or the Spider Globular, sits just to the right of Antares, the brightest star in Scorpius. And Antares is a variable star and a red supergiant. When viewed with the naked eye it's distinctly reddish in colour. It's often referred to as the heart of the scorpion, which I think is rather lovely.
Ezzy: So what you're saying is that you can see a scorpion and a spider together at the same time?
Katrin: Well, this is very true, yes. Hopefully we won't be able to see the heart or any heart of a spider. I was a bit freaked out thinking about the heart of a scorpion. To be honest, but um, I think it's quite a nice description when you think about it.
I know scorpions are quite ugly creatures, really, aren't they? But when it's up in the night sky and it's not...
Ezzy: I don't think so.
Katrin: Oh no? You're a scorpion fan?
Ezzy: Well I think... especially if you get one of the ones that are all black and shiny, I think they're quite... I'm not going to say cute or pretty. They're interesting. I'll say that.
Katrin: They are interesting. I certainly wouldn't want one like in my sleeping bag or anything, but yeah, in a pet shop or something, it's fine to look at.
Ezzy: Oh, I don't want to meet one down a dark alley. Definitely not.
Katrin: Well, there'll be one shining above you in the night sky. So, um, a giant scorpion.
You can see the globular cluster through binoculars or a telescope. It looks like a small, diffuse ball of light.
And this may be a challenge because M4 has a magnitude of +5.0, and remember, you know, we normally see objects of up to magnitude +7.0 in dark sky spots with the naked eye. And of course it's going to be next to like a nearly full Moon. So it's going to be quite difficult to spot. But worth getting out and having a look anyway.
Ezzy: Just a reminder for people who might be a bit more new to stargazing and aren't quite as familiar with with magnitudes: Magnitudes go backwards. The more positive a number is, the dimmer it is. So you want something that's either a small positive or even a negative. Those are the really bright objects in the night sky.
So a +5.0 object is actually quite a bit brighter than a +7.0 object. It's one of those historical artefacts that's been carried on for several hundred years and it made sense at the time and nobody's come up with a different system since, it's sort of stuck, so.
Katrin: We just go with it.
Ezzy: That's what we use.
Katrin: Yeah, accept it as it is.
After the excitement of the occultation, as the Moon approaches setting and tracks eastwards, it's going to glide under Antares by approximately 0.5º. I think a few of us will be in for a long night, but it will be worth it to see the occultation and the lovely pairing of Antares and the full Moon.
And while you're out on the night of 23rd or morning of 24th, take this opportunity to spot the Lunar Triangle on the Moon. So I wouldn't say it's a clair obscur effect because it isn't an interplay of light or shadow. The rays that connect the craters forming the triangle are actually features of the Moon. You'll need to use a pair of binoculars or a small telescope to spot the Lunar Triangle.
And as I just mentioned, it's formed by intersections of the rays from a trio of craters. So we have Aristarchus, Kepler and Copernicus. So if you can locate hexagonal shape Copernicus, which is situated slightly northwest of the Moon's Earth facing side, and then from Copernicus, draw an imaginary line diagonally upwards to the left to find extremely bright Aristarchus.
Kepler is located below Aristarchus and nearly opposite Copernicus and once you've found those three craters, you know, you can use the rays to draw that imaginary triangle if you like. You might need to use a Moon map or an app to help you locate them.
Ezzy: Yeah, there's lots of aids that can help you find your way around these sites. Especially with things like smartphones and apps and that sort of technology these days.
Because we always talk about the Moon in terms of, you know, what's casting shadow and the Moon's light on it, the phases come from the Sun's light on the Moon. And it is quite easy to forget that there's a lot going on. You know, it's not just a sort of light grey blobs and dark grey blobs.
There's a lot more detail on there that people can see that's sort of hard coded onto the moon, I suppose.
Katrin: Yeah, as I've, you know, I've mentioned before, I just think I love looking at the Moon. There's always so much to see or like if I'm reading a book or, you know, a web page and someone's mentioned something that's on the Moon, I'm like, oh yeah, I haven't seen that before, so I want to go out and take a look.
I do love the moon. I find it a real joy to look at.
Ezzy: You'd have to be watching it and observing it for a long, long time to get all the details and all the little different features on it.
Katrin: Yes.
Ezzy: So I know it was one of Patrick Moore's favourite things and he did an absolutely epic map. Up in our office, in the Sky at Night Magazine office we have one of his ones that I think he did back in the like 60s or 70s, we have a reproduction of that on the wall.
Katrin: Oh, that's amazing.
So just moving away from the Moon now, I'll talk about the Solar System. So, planet wise, the sky is pretty barren this week. We don't have Jupiter in the night sky anymore. Mercury, Venus, Neptune and Uranus are lost in the sun's glare.
But we do have Saturn rising in the east just before 3:00AM and Mars an hour later. And if you fancy getting out to observe the planets this week, be aware that you won't have long to make the most of any observing time because the sun rises at 5:07AM and Mars will be quite a challenge to see.
But challenge accepted. You know, astronomy wouldn't be any fun if it wasn't challenging, so get out there and see if you can spot it.
So on 23 May there is a conjunction between bright planets Jupiter and Saturn, but unfortunately this is going to happen too close to the Sun to be visible or even safe.
But you know, although we can't see it, it's always interesting to know what's going on in the daytime and nighttime sky.
Ezzy: Even if you can't see these meet-ups of the planets, it's still fascinating to know that they're happening. The reason why it's dangerous to see is because if it's happening very close to the Sun, it's incredibly difficult to be able to make out the planets without pointing your optical equipment – whether that's your eyes or a telescope – at the Sun, which is very dangerous and you should never do.
But it's still good to know that that's what's going on there and that's what the planets are up to at the moment.
Katrin: Absolutely, yeah, the planets are moving around all the time in their orbits. It's nice to know that these things are happening. So, we do have a comet on the scene that is creating some waves as well.
We have Comet C/2023 A3 Tsuchinshan-ATLAS, which is a bit of a mouthful there.
Ezzy: Yeah, comets are generally named after... they've got the sort of number part but Which is to do with about when they're found, so it's called C because it's a comet, 2023 because it was found in 2023, the A3 is the sort of which part of 2023 it was found in, and then it's the name of the person who found it, and it's Tsuchinshan, who I believe is a Japanese astronomer, and then ATLAS, which is a survey, so together I think they both found it.
Katrin: But this comet is predicted to be of naked eye brightness in September this year. It's currently in the western part of the constellation of Virgo, also known as the Polar Virgo. And it's currently magnitude +10.0, so obviously not a naked eye comet at all, and you will need a small telescope to see it.
We also have Ceres, a main belt asteroid, still hanging around this week. It can be located in the constellation of Sagittarius, to the left of the fabulous Teapot asterism, which rises at around 2:30 in the morning in the south. And asteroids aren't particularly bright, so you won't see Ceres with the naked eye.
You might be able to see it through binoculars if you know what you're looking for, or a small telescope. It's shining at a magnitude of plus eight again, so it's kind of not naked eye territory at all. Another asteroid that we have in the sky is Pallas, which is located between the constellations of Hercules and Corona Borealis, high in the southern sky.
It is at magnitude +9.10, and again, not naked eye, and you'll need a small telescope to see this too. So, you know, I think asteroid wise, you're going to need to know what you're looking for because they do just look like stars. And I'll be honest with you, if I was looking or trying to locate one, I would probably confuse that for a star.
And yeah. They're very tricky.
Ezzy: It's one of those things you really need to be looking kind of night after night, comparing it over time. And actually we've been tracking those asteroids in the previous couple of Star Diary episodes with Mary. So if people want to find out where it's been coming from, then go and back and listen to those.
And if you want to know where they're going, then you'll just have to listen into next week's episode as well. So always great to track asteroids as they move across the sky.
Katrin: Yeah, I was listening to Mary's podcast from the past couple of weeks, and it was really interesting. You know, she made the point of sketching the constellations as well, and then just kind of tracking the asteroid through sketch, so I thought that was really interesting.
Ezzy: Yeah, if photography isn't your thing, then there are other ways that you can record what's in the night sky. You can make a sketch sometimes if, you know, you've got a convenient landmark that's on the ground. I know quite a lot of people, they use, you know, like the rooftops around their houses to track the path of the Moon across the night sky and things like that.
So it doesn't have to be photography if that's not what floats your boat.
Katrin: Yeah, and I think people forget that in this day and age, don't they? Because there is so much technology and people think, "oh, I can't record this" or, you know, "I can't photograph that". But Old School, grab a piece of paper and a pencil and, you know, you can buy observing notebooks as well.
Ezzy: Yeah.
Katrin: That you can use. It's like an observing diary. It's definitely It's useful to remember that.
Ezzy: If you know which bit of the night sky it's going to be in, you can print out a star chart and then just mark on where you saw it and watch it over the night.
Katrin: I think it'd be interesting then at the end of the year if you were going to do that, you know, throughout the year just to kind of put it all together and you can have a nice folder of what you've seen over the past year. I think it'd be lovely.
So Ezzy. Would you like to see a hamburger in the sky?
Ezzy: Ummmm, pardon? A hamburger in the sky. I am intrigued.
Katrin: Yes. I wish that there was more food themed things in the sky to look at, but now is a good time to spot and make the most of some fantastic galaxies in the constellation of Leo, which is located to the right of the constellation Virgo.
And in Leo is the Leo Triplet, which consists of a small group of galaxies around 35 million lightyears away. And the best time to observe the Leo triplet is between March and May. And the galaxies in question are M65, M66 and NGC 3628, which is known as the Hamburger Galaxy. And these are all spiral galaxies.
Ezzy: Mmm.
Katrin: Yes.
Ezzy: Does it actually look what it's supposed to look like?
Katrin: It does, yeah. I mean, when I've seen pictures of it, it's quite long and squished. So yeah, it's as if you were looking at a hamburger on its side. So yeah, it looks like a hamburger.
In a dark sky spot, the galaxies can be viewed with a pair of binoculars or small telescopes, and to locate them, first find the star Theta Leonis, which makes up part of the back legs of Leo the Lion, then move down towards Virgo.
You're likely to land on at least one of the three galaxies, so missing the remaining two will be nearly impossible. And despite all three galaxies being spiral galaxies, you will notice that they all look different. And this is because they are tilted at different angles from our perspective on Earth.
And through telescopes with a longer focal length, it is possible to see all three galaxies in one field of view.
Ezzy: Ah! That's always nice when you can do that. It's sort of, when you're looking through the eyepiece everything gets so disjointed. That is one of the nice things about some astrophotography is you can, either by stitching together images or just doing wide field photography, you can get in these whole night skyscapes that you can't see through a telescope. But when you can actually see it for yourself that's always nice.
Katrin: Yeah, and three galaxies in one field of view. I think that's brilliant, isn't it?
Ezzy: That's one of those things when you think about how many stars there are in a galaxy and then there's three galaxies and then I have a little existential crisis, and have to go and sit in the corner and drink a cup of tea for a bit. But it is amazing that you can see that much in the night sky.
And thank you very much for taking us through everything that we can see in the night sky this week, Katrin. And if our listeners at home would like to keep up to date with all of the latest goings on in the night sky, please do subscribe to the podcast and we will be back here next week with even more stargazing highlights.
We start on 20 May when the waxing gibbous Moon and Spica are close together.
Then on 23rd we'll have a conjunction between Saturn and Jupiter in the morning sky, though unfortunately it will be hidden by the Sun. So you won't be able to see that one.
On 23rd into 24th, the full Moon and Antares will make a lovely pairing together.
You can use this opportunity to see the lunar triangle on the Moon, which is formed by rays between the craters Copernicus, Aristarchus and Kepler. There's also a lunar occultation when the full Moon will pass in front of globular cluster M4.
Throughout the week on the planet front it is a bit quiet. Mars and Saturn can still be seen in the morning sky for an hour or two before sunrise. However, Mars will be quite challenging to see at that time.
In terms of comets, we've got Comet C 2023 A3 Tsuchinshan-ATLAS in the western part of the constellation of Virgo. That will require a small telescope to see.
Asteroid Ceres can also be seen in the constellation of Sagittarius, and Pallas will be between Hercules and Corona Borealis, if you want to track those two asteroids.
And finally, it's a great time of year to take the opportunity to see the Leo triplet of galaxies, M65, M66, and NGC 3628. You'll need to find a dark sky spot, but those will be visible through binoculars.
So lots to be getting on with this week, and hopefully we'll see you all back here next week. Goodbye!
If you want to find out even more spectacular sights that will be gracing the night sky this month, be sure to pick up a copy of BBC Sky at Night magazine, where we have a 16 page pull out sky guide with a full overview of everything worth looking up for throughout the whole month.
Whether you like to look at the Moon, the planets, or the deep sky, whether you use binoculars, telescopes or neither, our Sky Guide has got you covered, with detailed star charts to help you track your way across the night sky. From all of us here at BBC Sky at Night Magazine, goodbye.
Chris: Thank you for listening to this episode of the Star Diary podcast from the makers of BBC Sky at Night Magazine, which was edited by Lewis Dobbs.
For more of our podcasts, visit our website at skyatnightmagazine.com/podcasts, or head to Spotify, iTunes or your favourite podcast player.
