Venus’s changing phases and Pluto at opposition are the highlights of this week’s stargazing guide. <\/p>
What\u2019s in the night sky in the week of 17 to 23 July, 2023 in our weekly stargazing guide. Venus\u2019s changing phases and Pluto at opposition are the highlights of this week\u2019s stargazing guide.<\/p>
Chris Bramley\u00a0<\/strong>Hello and welcome to Star Diary, the podcast from the makers of BBC Sky at Night Magazine. You can subscribe to the print edition of the magazine by visiting\u00a0www.skyatnightmagazine.com<\/a>\u00a0or digital edition by visiting on iTunes or Google Play.<\/p>\n Ezzy <\/strong>Greetings listeners and welcome to Star Diary, a weekly guide to the best things to see in the northern hemisphere\u2019s night sky. As we are based here in the UK, all times are in BST. In this episode, we\u2019ll be covering the coming week from 17 to 23 July. I\u2019m Features Editor Ezzy Pearson and I\u2019m joined this week by reviews editor Paul Money. Hello, Paul.<\/span><\/p>\n Paul <\/strong>Hello Ezzy. Nice to see you again.<\/p>\n Ezzy <\/strong>\u00a0Nice to see you. And what can we expect to see in this week\u2019s night sky?<\/p>\n Paul<\/strong> We start off on the 17th itself. Now it is in the morning sky, we\u2019re looking at 03:00 AM.. We mentioned towards the end of last week that Taurus is back in the sky, especially the Hyades<\/a> and Aldebaran<\/a>. Well, there\u2019s something else to look at near them and that is on the 17th and 18th, the minor world vesta.<\/span> This is the fourth one that was discovered, which is why it\u2019s called 4 Vesta<\/a> and it will be nearby to Aldebaran<\/a>. It\u2019s about a degree away from Aldebaran. You\u2019ll need binoculars. Vesta is at least +8.0 magnitude, whereas Aldebaran is easily naked eye, very bright.<\/span> You won\u2019t be able to mistake that, so it\u2019s worth having a look at. You do need star charts because obviously there are other stars in this vicinity as well. But the reason why we say 17th and 18th, you look for the one star that\u2019s moved.<\/span> To hopefully you get two mornings clear and you can compare the position. So draw the star positions, and then the next morning draw them again and then compare them and see which one has actually changed position<\/span> and that will be Vesta.<\/span><\/p>\n Ezzy<\/strong> And that\u2019s, in fact, exactly how they found most asteroids in the first place. Definitely when I was doing my degree, we had to take images and do what\u2019s called blinking. So those two images that were taken several hours, days apart and tried to see what part\u2026 what object it was that had moved across the night sky. So if you do fancy some astrophotography, maybe you can try that and see if you can see Vesta moving across the night sky as well.<\/span><\/p>\n Paul <\/strong>And of course, they did use that technique to find Pluto<\/a>, and we\u2019ll come to that towards the end. So, yes, that is a morning thing. And again, they won\u2019t be very far above the horizon, so that will have an effect as well. So bear that in mind. Now, 19 July, we\u2019re back into the evening sky. We had a challenge at the end of last week whereby you were trying to see Mercury<\/a>. Have another go on 19th. <\/span>And the reason why I\u2019m suggesting this is that the Moon has passed through new phase and will be an incredibly thin, slender crescen<\/a>t to the upper left of Mercury. So again, if you can\u2019t see the Moon, Venus is still in the sky.<\/span> So we\u2019ve got four planetary bodies hanging in the sky. They\u2019re very low down, 10:00 PM in bright twilight. We\u2019ll have Mars, which will be difficult. We\u2019ll have Venus, which is the one you should be able to spot first.<\/span> That should lead you to the crescent Moon. You got to remember the crescent Moon. It\u2019s very thin. When it\u2019s thin, it isn\u2019t actually that bright when it\u2019s an extremely slender crescent. And then to the lower right of the Moon, you\u2019ve actually got Mercury just above the horizon.<\/span> So it really is a challenge because they will set very, very quickly. This is now the problem with Venus and Mars. They\u2019ve been dropping quite rapidly towards the horizon as such, so they will be carrying around with Mercury, they too will drop to the horizon.<\/span> So this is not a very good apparition for it, but always think it\u2019s a nice combination. You\u2019ve got four planetary bodies there to see if you can see, so use binoculars. But as we always say, absolutely make sure the sun has set first.<\/span> That is golden rule for safety. Make sure the sun has actually set.<\/span><\/p>\n Ezzy <\/strong>At least in the evening sky. Once the Sun has gone down, you can be pretty sure it\u2019s not going to come back up again or lose track of time and it\u2019ll suddenly pop up like it would in the morning sky. So just make sure it has fully set, completely set. And then once that happens, get out there and try and find those four.<\/p>\n Paul <\/strong>Now, all this week, you can do something different with Venus. You have to remember that Venus is bright and Venus with care, can be spotted in the daylight sky. It\u2019s a challenge that Pete Lawrence has often mentioned in the magazine and we cover it in the July issue as well. Because Venus is doing something interesting. Throughout the month of July, the phase is diminishing, it\u2019s getting thinner and thinner.<\/span> So Venus is looking more and more like the Moon without the craters. But if we look on 19th, around about 05:00am, so the sun will be getting low. But if you work out well\u2026 I mean, if you especially if you got a Go-To telescope<\/a>, it\u2019s quite easy for got a Go-To.<\/span> I know it\u2019s lazy, but if you got a Go-To telescope, ideally do an alignment beforehand and then hibernate it. And when you bring it out of hibernation, just tell it, go to Venus and it\u2019ll take you to Venus.<\/span> Not literally, it won\u2019t fly off the Earth\u2019s surface, but you know what I mean. So it\u2019s an easy way of doing it.<\/span><\/p>\n Ezzy<\/strong> I don\u2019t see it as being lazy, I see it more as you are taking away some of the grunt work. If you\u2019re not trying to learn your way around the night sky, if you\u2019re literally just trying to do a project or something like that. You\u2019re just making your life a little bit easier. I don\u2019t think there\u2019s any shame in using Go-To to help yourself.<\/span><\/p>\n Paul <\/strong>Well, let me tell you a brief little story. Just the other week I decided there\u2019s a mount that\u2019s been set up outside all the time and I haven\u2019t really been using it\u2019s. It\u2019s been covered over because I\u2019ve been using some of the other more portable mounts. So I went back to it and when I looked at the date that I\u2019d changed the settings, it was July last year.<\/span> I went and used that to find Venus in daytime, and it wasn\u2019t in the eyepiece. So I thought, oh, this is serious. But it was in the finder. Just. But there\u2019s a little moral to this story now, make sure you haven\u2019t knocked the finderscope<\/a>, because I spent ages trying to find Venus, manoeuvring it into the centre of the finderscope, and it was nowhere near.<\/span> Eventually I had to realign at night the next night, then go back, and then I could find it and I had to realign the finderscope. But when I found Venus in the finderscope, it was easy as anything. And I used binoculars in the middle of the day to find\u2026 10\u00d750 binoculars and I found Venus as easy as anything.<\/span> So I mean, as we get towards the end of the month, the disc is getting bigger, so you will actually start to notice the crescent, even in 10\u00d750 binoculars. But obviously a telescope will make it more obvious.<\/span> So there you are. Start watching the crescent of Venus as it starts to shrink over the next few weeks. But bear in mind, it will gradually start to get closer and closer to the Sun as well. So again, we always have that caveat with the safety.<\/span> You must be safe because otherwise you could damage your eyesight permanently. <\/span>Now, just as twilight begins on July 20th \u2013 this is late evening, so it\u2019s literally border time, daytime and twilight.<\/span> We\u2019ll have the crescent moon. This is the 20th, remember. the slim crescent moon will be a bit more obvious, and it is virtually directly above Venus. So even if you can\u2019t find Venus, you should be able to find the Moon and then look directly below it and it\u2019ll be about just under seven degrees.<\/span> The moon north of Venus itself. Or above Venus, I should say. So you\u2019ve got the crescent Moon, and then if you put a telescope on Venus, you\u2019ll have a crescent Venus as well, so you\u2019ll be able to compare the crescents.<\/span> I love doing that because it reminds you sort of thing that Venus goes through phases just like the Moon does, sort of thing. It\u2019s the only planet that\u2026 Well, Mercury. But Mercury is a lot harder because, of course, it\u2019s always nearer to the glare of the sun, isn\u2019t it?<\/span> But Venus, you get a chance to see the crescent quite easily. So do have a go at that.<\/span> Finally. Well, we like challenges, and this is a big scope challenge. Now, anywhere from an eight inch upwards. I know some people have seen it with a six inch, but that\u2019s on the perfectly dark skies and in a less crowded area of the sky.<\/span> I\u2019m talking about Pluto, because Pluto comes to opposition on 22 July. Yes, it\u2019s magnitude 14.4. So this is why you need a big scope. So it\u2019s worth having a look at. If you\u2019ve never seen Pluto and you\u2019ve got a big scope, do have a look for it.<\/span> This is the time when Pluto now becomes visible throughout the actual night. And a bit like we mentioned, you remember we mentioned about Vesta and doing the blink comparator. We mentioned that Clyde Tombaugh actually discovered Pluto using a blink comparator comparing photographs or thing.<\/span> You can do the same thing. And that would be perfect to do this for Pluto again now, because it is moving very slowly against the background stars and so now visible.<\/span> You need it\u2019s low down in Sagittarius, so it\u2019s suffering a little bit from that. So there will be some reduction in the brightness because of the position in the sky. But if you look around about the southern point, when it\u2019s highest in the south, around about midnight by then, then you should be able to pick it up with a large scope.<\/span> And if you do I mean, admittedly it used to be the ninth planet, but now, of course, it\u2019s the first of the dwarf planets, so have a look at it. You never know if you\u2019ve got a big scope well worth having a look at it, as long as you\u2019ve got a clear southern horizon to pick it out.<\/span> It\u2019s nearly at the border, by the way, of Capricornus, so it\u2019s only just in Sagittarius<\/a> at the moment. But it is a challenge. So if anybody sees it or photographs it, perhaps contact the magazine.<\/span><\/p>\n Ezzy<\/strong> Yeah, exactly. There is a reason why Pluto wasn\u2019t discovered until the 1930s. It\u2019s not the brightest thing in the world, as you said, +14.4 in magnitude, but it\u2019s definitely one to check off because most people have seen all of the other planets.<\/span> Most astronomers have seen all of the other planets, but Pluto is the one that\u2019s a bit of more of a challenge. So, yes, if you manage to see that one or snap an astrophoto, we always like to hear about it.<\/span> You can find details about how to contact and send those over on our website, <\/span>www.skyatnightmagazine.com.<\/span><\/a><\/p>\n And thank you very much for taking us through all of the week\u2019s highlights Paul. <\/span>To summarise, on 17th and 18 July, the minor planet Vesta will be just above Aldebaran in Taurus.<\/span> You will need star charts to find that one. On the 19th, you can see Mars, Venus, Mercury and the Moon altogether in the night sky. They will be very low and won\u2019t be visible for very long, so look for those at around 10:00 PM.<\/span> Throughout the month, you\u2019ll also be able to see Venus\u2019s changing phases. They will even be visible in the daylight sky. But on 20th you can compare Venus\u2019s crescent with that of the Moon, as it will be directly below the Moon on 20th.<\/span>Then on the 22nd, Pluto will reach opposition in the constellation of Sagittarius. That one is a bit of a challenge. It\u2019s only +14.4 magnitude, so you will need a big telescope to be able to see it.<\/span> But that is the week\u2019s highlights. If you want to make sure to catch next week\u2019s highlights, do subscribe to the Star Diary podcast and we will see you then. <\/span><\/p>\n 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 pullout sky guide with a full overview of everything worth looking up for throughout the whole month.<\/span> 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.<\/span><\/p>\n