Star Diary: 21 to 27 August, 2023
What’s in the night sky in the week of 21 to 27 August, 2023 in our weekly stargazing guide. Saturn’s rings are disappearing, so make sure you don’t miss the planet as it passes through opposition in this week’s stargazing guide.
Chris Bramley: Hello and welcome to Star Diary, the podcast from the makers of BBC Sky at Night Magazine. You can subscribe to the print edition for the magazine by visiting skyatnightmagazine.com or to our digital edition by visiting iTunes or Google Play
Ezzy Pearson: Greetings listeners and welcome to Star Diary, a weekly guide to the best things to see in the Northern Hemispheres night sky as we are based here in the UK, all times are in BST. In this episode, we’ll be covering the coming week from 21 to 27 August. I’m features editor Ezzy Pearson and I’m joined this week by reviews, editor Paul Money. Hello
Paul Money: Hello Ezzy I’m looking forward to this week.
Ezzy: Ooh, do we have some good things coming up? Please do tell us what we’ve got to look forward to.
Paul: We always have good things, but it’s always nice to start off with something that’s in the evenings guy. ‘Cause we do often and, and it will happen over the next few weeks, there will be things in the morning sky that we have to start the week with, but we do, we start off in the evening. It’s one of those things that although we’ve got, Mars is technically in the evening sky, but it’s so low and so deep into the solar glare now that I really… it’s not worth trying to search for it. It is very, very difficult. However, the Moon is a slim crescent on 21 August. We’re in early evening twilight, and you need to look towards the west-southwest horizon about say half an hour after sunset, and you’ll get the crescent Moon and the earthshine goes along with it as well.
And if you see that it’s worth using binoculars on it and then just casually drift your binoculars to the right and slightly down and you might see the star Spica. This is probably the last chance to see that star, to be honest, because it is dropping into the solar glare and we will actually lose it. But I always like it when you’ve got not just the Moon there, but there’s something else to catch your attention.
And it is interesting that people like to see stars next to the Moon, or in some cases the planets as we know, sort of thing. What’s that star? It’s no star. It’s a planet. Well, this one actually, he’s a star, but deep in the twilight, that’s the tricky bit. That’s why I think binoculars are more likely to see it rather than with the naked eye.
So that’s the evening, the early evening. Nice and convenient for us sort of thing. Half hour after sunset for us to get started this week.
Ezzy: It’s also very good the Moon or is a great pointer towards things. So if you are learning your way around the night sky, knowing when the Moon is going to be near to a a major star is always a great way to sort of start orientating yourself in the night sky.
Paul: Yes, it’d be a worry if you can’t find the Moon. I mean, I’ll forgive you if it’s like New Moon, ’cause that that near be an eclipse, won’t it, sort of thing. A solar eclipse sort of thing. But we’ll have to wait until October until we get that sort of, and it’ll only be partial for the UK anyway, but not in America.
Ooh, they’ll have a good one, but that’s for later anyway, on 22 August, and this really applies for most of the week really. We’ve got two of the outer giants now rising earlier, and they’re visible. I mean, look around about 10 o’clock in the evenings roughly sort of like towards the southeast onwards.
And what you’ve got is Saturn and Neptune. And Saturn is naked eye, so it’s in Aquarius. You shouldn’t have problem actually spotting that. I was looking at it the other night, naked eye sort of thing. And it, it was later sort of thing, you know, in the night, but it was quite prominent. So you shouldn’t make… it is much brighter than all the stars around it so that’s the good clue sort of thing. But Neptune will need large binoculars or a telescope sort of thing because it is a lot fainter. So it’s not naked eye. Unless you’ve got exceptionally good eyesight and extremely dark skies. But I, I don’t know of anybody who’s seen Neptune with a naked eye.
But it doesn’t take much optical aid. I say a pair of binoculars ’cause it’s usually around about magnitude 7.8, 7.9. So that’s well within the range of 10×50 binoculars easily. So, you know, so we’ve got these two and they’re rising earlier. And this is in preparation sort of thing for Saturn’s opposition, which won’t be long in another couple of weeks time as such.
So there we are now. 23 August, and again, it effectively occurs all week, but if you leave it a bit later, say, leave it another hour. And amazingly, the other two giant planets come into view Jupiter and Uranus. So they’re quite late still sort of thing. So they’ll be very low down. Roughly in the east, northeast, but you’ll need an uncluttered horizon at 11 o’clock.
But obviously, if you like staying up nights, I mean, you know, you might work nights, you might come back at midnight or whatever, or perhaps going to work late. You should be able to see them if you’ve got a clear sky and no things on the horizon to clutter it like trees or buildings in most cases.
So there we are. So 11:00 PM onward, they rise with Uranus forming the shallow apex of a triangle with Jupiter and the Pleiades, Messier 45. Oh winter’s well and truly on the way. Now I know people are still having summer holidays towards the end and the kids will soon be going back, but for us astronomers, we can’t wait for those dark skies.
And August traditionally sees us that transition between the, the, the summer nights and finally getting proper darkness for an hour or two during August. So you know, that’s when we start getting excited about the sky getting dark again. Now 24th, we’re still in the evening sky and a little earlier, about half past nine.
Now I’m talking about half past nine because it, it’s the end of twilight really. So the sky will be a little bit light, but it will be anyway ’cause you’re looking for the Moon and the first quarter Moon light just to the right of Antares. Now Antares is a lot brighter than Spica And the thing about it is that this is in a darker sky, whereas we had the Moon next to Spica in bright twilight.
This time it’s in the towards the end of the twilight, so be a lot more prominent. But it is around about the la the first quarter phase of the Moon. So the Moon looks like it’s chopped in off sort of thing. So you know, I always think it looks quite funny when you see it chopped in off like that.
But you wanna be looking towards the southwest horizon. And the Moon is effectively in the main front part of Scorpius itself and say to the right of Antares, and if you do have a look at it, have a look at binoculars and just note the color of Antares. It’s an orangey red star sort of thing. One of the classics as such.
Ezzy: Yeah, it’s a… Antares is, , along with Betelgeuse as well, or Betel- guys the two big red giants that you can quite clearly see in the night sky. So definitely keep an eye out for that one.
Paul: Interestingly, you have a job to see them both at the same time. In fact, physically you can’t see them both at the same time.
Ezzy: Exactly.
Paul: It is a nice point that, of course the story of Scorpius and and sort Orion is that the scorpion bit Orion. So they decided to separate Orion and Scorpius. So Orion’s literally 180 degrees away from Scorpius. So they, they never can meet. Never the twain can meet.
Ezzy: When one’s coming up the other one’s going down.
Paul: Yes, exactly. Now, finally, at the end of week on Sunday, Saturn is at opposition. Now when we talk about opposition, Saturn is opposition and it means it’s opposite the sun in the sky. So, funny enough, we just talked about sort of like Orion and Scorpius, and when one sets the other rises. This is almost, you could say Scorpius is in opposition to sort of like Orion in the winter and in the summer Orion is opposition to Scorpius. You could argue that. But it means as the Sun sets. Saturn will rise. It is opposite the sky and it’s visible all night now, which is really great. Now, if you use binoculars on Saturn, there is a hint that is elongated. It it, it’s very tiny, but your binoculars are not wrong -’cause obviously if you look at stars in the elongated, you’ve got a problem with your binoculars.
Ezzy: Yeah, you probably wanna get those checked out.
That’s a good clue, isn’t it?
Paul: Yeah, you know, so look at the other stars, make sure they’re nice dots sort of thing. Point it at Saturn. If Saturn looks elongated, you’re actually seeing the effect of the rings. Now, enjoy that while you can. ’cause over the next few years the rings are steadily closing up and so there’ll call a point whereby Saturn will be without rings for a short period, which is always uncanny and weird. Also makes the planet appear a lot fainter. ’cause it’s surprising how much light the rings put out.
Reflect back and boost up the brightness of the planet. So if you use a telescope, you can zoom in, of course, on the planet it’s getting well placed now to observe and it’s higher up the ecliptic. We already mentioned, it’s in Aquarius. So this is much better than it was just a few years ago when it was down in Sagittarius and you’re in the murk of the low atmosphere and it didn’t rise very high.
So planetary imagers are now getting better images of Saturn ’cause it’s a lot better placed. I can’t wait to have a go myself. So I need it to just get in to the right position with all the shrubbery from the neighbours, et cetera. Sort of thing. You know, I have to pick my moments, you know, and time it to perfection.
But there we are. If we get Saturn look at it with a telescope the bigger the telescope, the more moons you’ll see. Binoculars technically can show you Titan. Now, that particular evening, about 10 o’clock on 27th, Titan… Now if you’re using binoculars, it’ll be to the left of Saturn, but in most telescopes the image will be flipped.
So it’ll actually be on the right hand side, but Titan is almost at its furthest away from Saturn in this particular… when it’s almost lined up with the ring system sort of thing. So you follow a line through the planet, through the rings off, you actually find it’s close to it’s point on the side. So it’s on the east side of Saturn at the moment.
Now use the magnification of the telescope. Bigger the telescope, the more moons you’ll see. So there’s quite a few. There’s Rhea, Tethus, Dione and Iapetus are the ones that I usually see on a regular basis, but a bigger telescope might pick out Mimas, Enceladus and even Hyperion. I’ve seen, I find Hyperion better when it’s close to Titan, ’cause Titan then guides you to it. Just like use the Moon. It’s the same principle. I mean, use things that are brighter. To guide you to fainter targets, but now Saturn is at its best sort of thing. I think that’s a great way to the end of the week, isn’t it, sort. We’ve got Saturn at its best now rising and visible all night for those who like to stay up of course all night.
Ezzy: Yes. We actually have a guide… ’cause another way if you want to try and see some of those moons, if you perhaps don’t have a bigger. Telescope is, you can also do some astrophotography do a nice long exposure. And that brings out some of the moons. And we have a guide on how to do that in our August issue.
So you can look back at that or on the website. I will put a link to that in the description down below. But I’m not actually, because both certain and Jupiter have a lot of moons, I… it’s quite hard to keep track because they keep adding new ones and so they keep overtaking each other for which has the most.
And a lot of those moons are… it’s a lump of rock that’s going around. The planet. Some of them are only a couple of kilometers across, I think, even. But yes, I think the fact that you can see these tiny things orbiting another planet at such a huge distance is, is always fascinating to me.
Paul: It’s interesting, isn’t it, that with astrophotography we are now getting to a stage where we can pick up… I mean the, the newly discovered ones really need a massive telescope. So, you know, and it is Hubble usually that does that.
Ezzy: There’s, there’s a reason we’ve only just discovered them.
Paul: Yeah, exactly. So, but a lot of the ones that have been known for a while, it’s surprising with astrophotography how amateurs are now beginning to pick up these fainter, some of the fainter moons. Hmm. So, I mean, traditionally we would say for Saturn around about eight or nine moons. And that’s the maximum. You could probably double that now with amateur astrophotography sort of thing.
And the same goes for Jupiter. A lot of the fainter ones, you have to know where to look. But you know, it’s a, it is surprising what you can actually see now. But well visually, if you’ve got a large telescope, you are all right, sort of. You might be able to pick out one or two of the faint ones, but photography’s totally changed things, hasn’t it? They’re so sensitive these cameras.
Ezzy: I think especially as we are going forward into a period where… because the moons of… everybody talks about the moons of Jupiter and the Galilean moons, but nobody ever really sort of seems to talk about the fact that you can see the ones around Saturn as well because they get a bit overshadowed by the rings.
And as we’re moving into a period where the rings aren’t gonna be as good maybe it’s the chance to not just forget Saturn entirely, but but pay a bit more attention to the moons going around it instead. I think that would be a nice little project for people if they feel like something over the next couple of years.
Paul: Yeah and with the rings closing up, there isn’t as much light. So the inner ones, Mimas and Enceladus are always difficult ’cause of the glare from the rings. So when you’re doing the imaging, the rings burn out and they burn out and they… burning out means it expands. The image area has expanded, so it covers usually Mimas Enceladus. Whereas as the rings aren’t producing as… putting out as much light now, ’cause they’re closing up, it becomes easier to see Mimas and Enceladus. So I’m looking forward to that ’cause I have imaged them, but they’re really tricky because they’re so close to the rings themselves.
Ezzy: And of course if anybody at home does manage to take any good pictures of Saturn or any of the other planets or things that we’ve talked about today, please do feel free to send them into the magazine.
You can find the details of how to do that on the website. We print the best ones in the magazine every month, so hopefully we’ll get to see yours soon. But thank you very much for taking us through that week, Paul.
Paul: Thank you.
Ezzy: So to quickly resummarize those on 21 August, the Crescent Moon will be near to the star Spica so a great chance to be able to find that.
Then on 24th Antares and the half Moon will be together if you want to try and capture those. Throughout the week in the evening sky, we will have all four gas giants. Jupiter Saturn, Uranus, and Neptune will be visible at some point throughout the night, but on 27th, that is the date that you want to put in your diary because that is when Saturn is going to reach opposition and it’ll be visible throughout the night.
So lots of things to be getting on with this week and hopefully if you want to find out what’s going on next week, do join us for the next episode of Star Diary. Goodbye and hopefully we’ll see you then.
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. For more of our podcasts, visit our website at skynightmagazine.com or head to Acast, For more of our podcasts, visit our website at skynightmagazine.com or head to Acast, iTunes or Spotify.