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Today we are going to take a look ahead into the coming month of August and of course, we have been looking ahead into the coming month of August all year long because August 12th is the date of the total solar eclipse that’s going to be visible across a large portion of Europe as a partial eclipse, and in Spain and Iceland as a total eclipse.

To begin, we are looking at sunset on the 2nd of August, with Venus still in the sky as the Sun goes down, but very low to the horizon. August 2nd is also the greatest western elongation of Mercury, so we will come back to sunrise on the 2nd and see if Mercury is visible to us. Of course we know that Mercury is visible to us, because we had a look at Mars and Saturn in the morning in July Mercury was visible then. That was before its greatest elongation, so of course it’s likely to be visible in August when it reaches that greatest elongation. Mercury is visible fairly clearly while it’s low in the sky. If you have a clear view to the east, it should be visible, but could be obscured by trees or buildings. As Mercury gets higher, of course the Sun gets brighter and it does get more difficult to see. As we move forward Mercury gets brighter, although it is getting lower in the sky as. Continuing into the month, Mercury will be having a very close conjunction with Jupiter on the 15th, but again very low to the eastern horizon.

Taking a closer look, Mercury and Jupiter are very close together. They are still visible as they get a little higher in the sky, but of course there is a lot of light from the Sun by then. Through many telescopes the circle of Mercury and some of Jupiter’s moons would be visible. We would have to look a little bit closer at Mercury to see its phase, by the 15th it is practically full, which is one of the reasons it’s getting brighter. If we move back to its greatest elongation on the second, we’re looking at more of a half Mercury. Not as much of the face of Mercury that is illuminated is facing us, so we’re not seeing as much light from Mercury. Even though it gets further away from us, as we move towards the 15th, more of its illuminated face is facing us and that makes it a bit brighter. Pulling back, we’ll take a closer look at Jupiter as well. Some of Jupiter’s moons are nice and close together, like Io and Europa. As we move later in the month, from some locations, there will be occultations where these moons move in front of each other. Just taking a quick look it doesn’t look like we’re going to be catching them from here in Ireland, but we can see all four of the Galilean moons, once we zoom in enough.

We’ve moved through to the 15th from Mercury’s greatest western elongation on the 2nd. It is up in the morning looking to the east, because it’s west of the Sun. On the 15th we’re also going to have the greatest eastern elongation of Venus, which means we will see it in the west at sunset. Unfortunately, Venus isn’t very visible to us, even though it is technically further from the Sun than it was at the start of the month. This is because Venus is getting lower in our sky. As Venus orbits the Sun, its orbit isn’t at the same inclination as ours, so Venus does appear to come around the Sun and then sink down as it goes in front of it. We can see here that Venus is getting brighter as we move forward. As we move back, it’s getting fainter, as we move forward, it’s getting brighter. If we take a closer look, we will see that Venus is getting less than full as it gets brighter. We’ll move back and Venus is a little bit fuller. As we move back, Venus is getting fuller, as we move forward, it’s getting less full but it is getting closer to us, and that’s what makes it appear brighter.

Venus and Mercury work the opposite way in this regard. When Mercury is further from us, more of its illuminated face is facing us, so it looks brighter, when Mercury is closer to us, more of its illuminated face is facing away, so it looks fainter. With Venus, because Venus is further from the Sun than Mercury, it’s able to get further from us on the far side of the Sun and closer to us on the near side of the Sun than Mercury can. Due to this, when Venus goes around the Sun, when it’s further from us, it is fully illuminated, but it’s so far from us that it appears fainter. As Venus comes around the Sun, we’re seeing less of its illuminated side, but it’s so much closer to us that it seems brighter anyway. Those are the two elongations that we’re getting, one at the very start of the month and one around the middle of the month on the 15th.

If we move back to the 12th, of course, the 12th is the date of the eclipse and we will take a quick look at the eclipse in just a moment, before we do, we will take a look at the Perseid meteor shower. I will speak more about the Perseid meteor shower once we get a little bit later into the month. The radiant of the Perseids is fairly high in the sky, being in the constellation Perseus. Technically it peaks on the 13th, but after sunset on the 12th the zenith hourly rate is 93. If we move forward to the 13th at the same time, it’s only seeing 69. If we move forward through midnight on the 12th into the 13th, that brings us to the peak. We’re looking at the morning of the 13th rather than the evening of the 13th, at about 3:15. At that time, the predicted zenith hourly rate of 100 equals the maximum zenith hourly rate of 100. However, the Perseid radiant is not at the zenith, so we’re only seeing about 40, plus the light pollution is also a limiting factor. One good thing, because this is happening after the solar eclipse, we know it’s happening around the New Moon, so the Moon won’t be there to interfere.

If we move later, the Perseids do get closer to the zenith, so the amount that we’re seeing goes up to 44, but the actual zenith hourly rate goes down to 96. Also with the rising Sun, that’s going to block out more of the meteors. On the 12th, as soon as the Sun goes down, the Perseid meteor shower will be providing more meteors than the Southern Delta Aquariids did for us at as close to their peak as we could see. We only got to see a few, about nine, and all of the meteor showers happening at the same time added together only provided us about 16. The Perseids meteor shower at sunset could have rates as high as 20, and we’re getting up to 42 before sunrise even in the city. If we move out to a perfect countryside sky, that climbs to 87. Very early in the morning, Stellarium shows rates of up to 92, but with the light of sunrise in the sky, I don’t think we’d actually be seeing 92 at that point. At around 3 o’clock in the morning, we’re getting rates in the high 80s, up to 90, so a dark sky will make a very big difference.

As well as Mercury, and Venus, and the Perseid meteor shower, we do of course have the solar eclipse and it is happening on the 12th. If we move late at night to day time on the 12th, there will be a period of dimming. Just before the Sun goes down, the sky gets darker and then brighter again before the actual sunset. That is the eclipse. From here in Ireland, it’s not a total solar eclipse, I will go through the view of this eclipse from locations where it is total before the 12th, I will address that a couple of posts time. Firstly, we’re going to move back just a little bit to see this eclipse beginning from here in Ireland at just after six o’clock, about 6:12. Around 6 o’clock or maybe 6:10 would be a good time to start observing this eclipse. With the correct protection, of course, you need to use solar eclipse glasses or observe the eclipse indirectly using a pinhole camera. Coming up to our maximum, over 90% of the Sun will be obscured. At just a little after 7 o’clock, we’re getting up to 96% obscured at just 7:12. About an hour after the eclipse begins, that’s when we’re going to see its real maximum. Of course, for a large portion of the beginning of the eclipse and the end of the eclipse, not enough of the Sun is going to be obscured for it to be very obvious. As the eclipse ends a little after 8 o’clock, it is likely to drop behind trees or buildings.

As the eclipse ends, we miss the end of it, and of course we don’t get to see it at a hundred percent totality. However, this is going to be a really good eclipse from Ireland, it’s not too low in the sky and we’re seeing it here at just 7 o’clock. If you know anywhere where the Sun shines at 7 o’clock, where there isn’t a shadow at 7 o’clock from trees or buildings, if you can stand in a place where the Sun is shining at you at about 7:15 and you have the correct eye protection, you should be able to see this eclipse from here in Ireland. Even if you don’t have the correct eye protection, you might be able to spot Venus. You can’t look directly at the eclipse without using special eye protection, but Venus is pretty far from the Sun towards the south. If we turn off the atmosphere, we’ll see Venus getting a little further away as we come up to its greatest elongation 15th. We wouldn’t be able to see Venus during the day with the atmosphere if not for the eclipse. They are very far apart, Venus and the Sun, but unfortunately they’re just not at a very good angle for us to see from here in Ireland. Thankfully, the eclipse and the Perseid meteor shower really are.

I hope you get to see some of these events in real life and we will take a look at the planets again in a future post, again before the 2nd of August, just to give you a better idea of how they will look if you are from lower latitudes. Until then, I hope that you enjoyed this post. If you did, please do like it. If you like this kind of content, then please subscribe to this website and my YouTube channel. Thank you very much for reading and hopefully I’ll see you back here next time.