Caoimhín's Content

Today we are going to continue looking at the coming month of August. We’re going to take a look more at the stars, the constellations and how they’re going to change, but we are also going to take a look at the greatest elongations of Mercury and Venus from more favorable locations.

If you remember from the previous piece, the elongations of Mercury and Venus aren’t going to look fantastic from here in Ireland, but they will look better from other places. The month of August is jam packed, there’s lots happening, so if you didn’t catch the last piece, I urge you to take a look. We’re looking from a city sky with the close to Full Moon on the 2nd. If we take a look at the percentages it’s 82%, so quite full but not 100% full. It’s still quite bright, enough to block out fainter objects.

We’re still seeing a little bit of light over in the west for a bit after sunset because we’re so early in August, but it won’t be long before that twilight glow disappears from our sky at nighttime. We can see Boötes or at least we can see Arcturus, part of Boötes, getting quite low to the west. Scorpius is also getting towards the southwest and Sagittarius is now due south just before we come up to midnight. If we push ahead to midnight, Scorpius will be pretty much setting, Antares at least is below the horizon. Sagittarius is visible but already past due south and the Summer Triangle is still in the zenith of the sky. If we move forward we’ll see the Summer Triangle is still there, disappearing in the morning as the Sun rise. It hasn’t yet vanished from view before sunrise. So this early in August it is still considered summer according to the Summer Triangle. If we move forward later into August, of course the sunrise will be getting later so the sky will be darker until a later time, even at 5:15 it’s still quite dark once we’re through to the end of August. By then, the Summer Triangle is setting before the Sun rises. That is our sign that we are out of summer according to this astronomical teller of the time. We’ll move back a little bit into darkness and come back a little bit closer to the beginning of the month. As we do, the Moon passes by Saturn and then Mars, but they are not particularly close conjunctions.

The square of Pegasus is also visible nice and high in the sky in the morning, clearly above Saturn and we are getting back some of those wintertime constellations like Gemini and Orion just before sunrise. If we move back later in August, we’ll have Orion above the horizon before the Sun rises, clearly observable at just about 5 o’clock, and Gemini will be clearly above the horizon as well. Jupiter will also be returning to the sky in the morning. We’re definitely getting back those wintertime constellations once we get through to the end of the month and we’re going to lose the summer triangle before sunrise once we’re through to the end of the month as well. These are all signs that we are getting back into winter time. Taking a look at the early evening sky just as we come towards the end of the month, we’re still getting a little bit of Scorpius and Sagittarius as the sky gets dark, but not for very long. This means the core of the Milky Way is already going to be dropping down into the southwest at just 10 o’clock.

Of course, we’re not going to see that in the city, so we will head out to the countryside and we’re barely seeing it early in the evening. There’s still a little bit of light from the Sun, and the Moon is quite bright as well. If we move a little bit later, we can see it a little bit better as the sunset glow fades away, and if we move a few days ahead, the Moon gets out of the wayn as well. After moving into the start of September, at just a little bit past 10 o’clock, the core of the Milky Way is visible but already starting to set under the horizon. As we come back towards the beginning of August, we have to wait until a bit later before the sky is dark enough for the Milky Way to be visible, but the core will be up for a little bit longer. Early in August, for example the 9th, the galaxy is still very clear in the sky. The core of the Milky Way is up early in the evening, rather than having to wait until morning time, and the sky is actually getting dark. There is a little bit of a glow in the northwest before we reach midnight, but if we move forward, that light is definitely gone and the Milky Way is still there, stretching across the sky. This is is a great time of the year to look for the Milky Way, which in all honesty is something that looks a little bit better from lower latitudes as well, just like the greatest elongation of Venus on the 15th.

As we move forward from the 15th, Venus does get brighter, but it’s getting much lower in the sky. From the countryside we will be able to see Venus for a little bit longer because there’s no light pollution, but of course, with light pollution complicating matters, we’re not going to see much of Venus at its greatest elongation. It’s appearing in the sky, from Ireland, at about the height of a telephone pole, or an electricity pole maybe. If you have any buildings or structures around you that are taller than that towards the west, they’re going to pretty much obscure Venus from view unless you are at a location high enough to look over them. That’s one of the benefits of living in a tall building, you can see over some of the buildings around you and get a slightly better view of the sky. The roof of a tall building of course is good for that as well, but do be careful.

We will move down to lower latitudes, we’ll start by moving just to the south of Europe, down towards South Spain. That’s already going to bring us closer to the equator and Venus is visible in much greater darkness. When Venus first appears, even with light pollution, it’s significantly higher in the sky, at least twice as high. We’re looking at Venus at its greatest elongation, it is higher in the sky before this, when Venus appears closer to the Sun. If we move forward, as Venus comes around the front of the Sun it gets much brighter and it’s visible at that much increased brightness for far longer when we’re closer to the equator.

We’ll move back, firstly towards morning time and then towards the beginning of the month in order to get back to Mercury’s greatest elongation. Mercury is always a difficult planet to spot, but its greatest elongation gives us one of the best opportunities. Just before sunrise on the 2nd, it’s quite high in the sky, just disappearing by about 4:30 now that we’re closer to the equator. It’s quite visible in a fair level of darkness at just about 4 o’clock in the morning. We’ll move forward to the 15th again, you may remember from the previous video that, even from Ireland, Mercury and Jupiter had a fairly close conjunction on the morning of the 15th. We’re still only seeing them quite low in the sky, but we are able to see them with a slightly greater level of darkness from Spain.

This conjunction between Mercury and Jupiter, it does seem like the kind of thing that will look much better from closer to the equator, but even at 30 or so degrees north, Mercury, Jupiter and some of Jupiter’s moons are visible in a fairly small field of view. Jjust to double check, we’ll zoom in on Jupiter with a telescope. Starting with quite a big powerful telescope, that will actually limit our view. A big powerful telescope will give you a great close up of a particular area, but only a small area, showing either planet but not both. Stellarium will only simulate a telescope view if you have an object selected. With a real telescope, you would have a greater degree of flexibility because you would be able to focus on things in the exact center and try to see Mercury and Jupiter slightly to the sides, but it looks like you would need a very precise level of magnification. Simulating a Meade ETX80 with a 14 millimeter PLOSSL lens, that’s able to show us some of Jupiter’s moons and Mercury at the same time. It’s less magnification than a big telescope, but with a wider field of view. Also in reality, the Earth is turning, so the planets will drift across your field of view and you need to adjust to keep them visible. Just before we finish up, we will go towards the equator. We’ll go much closer to the equator, but not all the way to the equator, in order to get a, no doubt better, view of those conjunctions.

Even much closer to the equator, Mercury and Jupiter are still very close to the Sun on the 15th. Even though we’re much closer to the equator and the angle of the ecliptic is more favorable, they’re still a little bit tricky to see. Moving back to Mercury’s greatest elongation, however, and it’s significantly higher in the sky and it’s visible with a really good level of darkness, a little low in the sky, but still better than the view we would get here in Ireland or even in Spain. Moving back towards evening time and then back to the 15th to Venus’s greatest elongation. Venus is visible nice and high in a great level of darkness when it appears first in the sky, just as the Sun is going down. As Venus comes around in front of the Sun it gets brighter, and despite getting a little lower, it’s still staying much higher for much longer than it did for Spain. It’s up all the way into October, when Mercury and Venus pass by each other after Mercury comes around to the sunset side of the Sun. We’re looking at it here from Africa at about 10 degrees north, but anywhere near the equator will give you a similar view.

They are the two greatest elongations and those events do look a little bit better from lower latitudes. There is a good chance that the Perseid meteor shower will look better from a different location as well, which is something we’re going to take a look at in an upcoming piece. Until then, I hope that you enjoyed learning what these planetary elongations are like from better viewing locations, and I hope you get to see them in real life, regardless of what location you’re in. If you enjoyed this piece then please do like it and 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.