Caoimhín's Content

Today we are going to be looking ahead to the coming month of September, but just before we do, I want to remind everyone of the partial lunar eclipse that is occurring on the 28th of August. We’re starting on the 27th and moving past midnight. Around 2 o’clock the shadow of the Earth will begin passing onto the Moon for us here in Ireland, the penumbra of the Earth should be visible by 2:45. This eclipse is visible from the Pacific coast of North America all the way through to Central Europe. We are coming up to the peak of the partial eclipse at about 5 to 5:30, in the morning. About 5:10 is really the peak and then the eclipse will begin to finish. We won’t catch quite the end of it here in Ireland because the Moon will be setting. For other locations, for example, Bermuda in the Atlantic, they’ll get to see this eclipse the whole way through, but it will be a partial no matter where you are. So just to remind everyone of that upcoming lunar eclipse in August before we move through to September.

We’ll move on to the 1st of September and we’ll come back to sunset. Of course the beginning of September won’t be too different from the end of August, we’re still going to see Scorpius in the southwest just after the Sun sets, and we have Sagittarius fully above the southern horizon. A little bit higher in the sky we still have the summer triangle, but of course it is going to set before the Sun rises. We still have Arcturus, part of Boötes, it’s still in the sky for now. We can see the Plough or the Big Dipper over in the northwest pointing down to Arcturus. You would be able to spike on to Spica, but it’s below the horizon in Ireland. We’ll keep moving forward, with Saturn coming up very early. Saturn is going to reach opposition a little bit later in October, but Neptune is reaching opposition at the end of September. At the start of the month, we’re quite far past midnight by the time Saturn is approaching due south. If we zoom in a little bit, Neptune is still quite close to Saturn in the sky. Saturn is going to reach its opposition once we get through to October, Neptune is just a little bit before that in late September. Taking a closer look, Neptune’s largest moon Triton is visible, and taking an even closer look, some of the other moons are visible as well. Of course, Neptune is an incredibly distant planet, it is very hard to see, but the date of opposition is the best date to try. That’s coming up at the end of September, so we will get back to that shortly.

Looking at the sky around 2 o’clock, the square of Pegasus is nice and high in the south. As we look down towards the northeast, we have Mars coming back with Gemini, and we’re starting to see the top of Orion. Of course, they’re going to be much more visible once we come up to morning time and Jupiter is nice and clear in the morning as well. There is something happening with Jupiter on the 9th of September, but we’re going to take a look at that in a future piece. We’ll take a look at Saturn and Neptune in another piece further in the future as well. This is just the start of September, once we come up to the 11th of September, that is the date of our New Moon. September this year is a quieter month. August was a very busy month astronomically, with the eclipses, solar and lunar, as well as the Perseid meteor shower. Now that we’re into September, things are going to be a little bit quieter, but we are getting back into winter, so our nights are going to be getting longer and of course, we have the equinox in September as well.

We’re going to quickly move out into the countryside for the 11th, for the night of the New Moon, quite early at just 9:30. The glow of the Milky Way is visible, stretching from between Sagittarius and Scorpius up through the summer triangle, past Cassiopeia, and down the other side. We can still see the glow of the Milky Way just after sunset, but as we move forward, we’ll see the core of the Milky Way is setting quite early. This is in a perfectly dark sky, of course we won’t be able to see this in the city, but by midnight on the clock, the core of the Milky Way has pretty much set, we’re mostly left with the fainter outer arm. A fair bit of the core is still visible in Stellarium because we have a reasonably flat horizon towards the southwest and the west, but of course if you are in a real area with mountains and hills, that’s going to be even harder to spot. We’ll come up to 1 o’clock and a little bit after 1 o’clock to get to our physical midnight. We are still in summertime this early in September, so we are off UTC by one hour. By then, all of the core of the Milky Way has set, we’re really just left with that fainter outer arm. That’s going to be happening earlier and earlier as we get through September and as we push back into winter time.

Pushing back towards 2 o’clock, Saturn is getting up to the south a little bit earlier. If we push back a bit, Neptune would be getting to due south a little bit earlier as well. When planets come to opposition, they are directly behind the Earth in the middle of the night, the physical midnight, not midnight on the clock, so we will have to adjust for that. Now that we’ve pushed through to morning time, still in the countryside, still early in September, we’ve got a great view of several planets. Of course, Neptune would be there as well as Saturn, then Uranus, Mars and Jupiter. Uranus really does take at least a binoculars, if not a telescope, to view, Neptune certainly takes a good binoculars, if not a telescope. We can see Gemini very clearly just before sunrise, all of Orion is above the horizon and Sirius has now rejoined the sky in the morning. The Hyades and the Pleiades, both in Taurus, are up pretty high at 5:30 in the morning and the glow of the Sun is just starting to come into the sky and block things out.The sickle of Leo is just ahead of the Sun, with that constellation moving out from behind the Sun at this time as we move around the Sun.

That is the 11th for the New Moon, the Full Moon in September is pretty close to the equinox. We will come back into the city and then we will jump forward in the month. As I mentioned, September is a quieter month, so we’re coming forward to the 23rd to get the equinox and the Moon is going to be coming up to full, reaching full on the 26th. Venus is technically still there, if we get rid of the ground and the atmosphere, both Venus and Mercury can be seen. For people closer to the equator, they would still be visible, but they’re out of view for us here in Ireland by the end of September.

As we move forward, by the time it gets dark it’s not even 9 o’clock. We’ll let it come up to 9 o’clock for a good level of darkness. The summer triangle is already directly above the south, we’re not going to see it for the entire night, it’s very clear even early in the evening that the summer triangle is already too far across the sky. Saturn is already up and visible, and as I mentioned, the Moon is coming back to full. That extra light of the Moon is going to make things harder to see. As we push forward, first to midnight on the clock and then to our physical midnight at about 1:30, Saturn and Neptune are practically above the south. Neptune actually reaches its opposition on the 25th, so we will move forward to the 25th soon to take a look at that. As we move forward to morning time, even from the city, the sky is still nice and dark at 5:15. All of Orion is above the horizon as are Sirius, Gemini and Mars. We have a great collection of these things that are normally visible in winter time, we are getting back into wintertime so they are going to get more visible. The brighter stars are still visible until almost 6:30 from the city. Of course, Jupiter will stay visible a little bit longer given that it is so bright, it’s still there, nice and obvious, almost as we come to 7 o’clock in the city.

We’ll come back to sunset and firstly we’ll hop forward to the date of the Full Moon, which is coming up just at the end of the month. On the 26th it rises at 99.9%. and because we’re seeing it at 99.9% here, I wouldn’t be too surprised if we do get to see it at almost 100%. It’s very close to Saturn and Neptune, close to the date of opposition, and it goes down to 99.7% as we move through the night. We’re not quite seeing the Moon at a hundred percent, but that’s okay, we’re not going to miss out on a lunar eclipse, given that we just had one. We’ll come back to when the Moon was rising when it was still 99.9%, that’s as full as we’re going to get the Moon this month. It is 374,000 kilometers away from us, so it’s not quite close enough to be a Supermoon. It is after drifting a little further away than what would qualify for a Supermoon, which is about 360,000 kilometers away or less.

We’ll take a look here, not at Saturn, of course, its opposition isn’t coming up until October, but at Neptune. With the light of the Moon, it is going to be difficult to see. Looking at Neptune, it’s illuminated 100%, which is a sign that it is at its opposition, we’ll come back to the 25th and it’s still at 100%. We can see that its distance from the Earth is at 4,319 million kilometers, so that is of course, pretty far. We’ll see if that gets closer, a little closer there on the 24th. So presumably it’s just after midnight on the 24th that Neptune actually comes to its opposition, its minimum distance of 4319.723 million kilometers from us. Still really far away from us, that’s 28 AU, and between its very closest and either side of its very closest, we can see that the AU’s don’t really change. That’s because that measurement is just so big. The slight difference of, you know, few thousand kilometers won’t make a difference to the AU. That is going to be the best night to take a look at Neptune, except for the fact that the Moon is going to be there, quite close to Neptune in the sky on the 24th as it comes up to full on the 26th.

That pretty much brings us through September. We’ll take a closer look at the stars as well as Saturn and Neptune in a future piece and we’ll talk more about the equinox in a future piece as well, I know I kind of skimmed over it this time. I hope you enjoyed this piece, if you did then 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.