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Today we’re going to revisit the Southern Delta Aquariids, which are the main meteor shower that we are going to be seeing at the end of the month. I briefly mentioned this meteor shower, and some of the other meteor showers that we’re going to see, at the beginning of the month in an earlier piece, but we’re going to take a closer look at them here. Moving up to 3:30 in the morning, we have several radiants above the horizon. These radiants are where meteors will radiate from during these showers. There are always some amount of meteors in our sky. Directly behind the Earth is the antihelion point, a place in the sky where meteors are that are falling through space get caught by the Earth’s gravity and pulled into our atmosphere. It has a zenith hourly rate of about 4, and a local hourly rate of about 1 because it’s so low in the sky. Although there are meteors radiating from it, a lot of the meteors are going to be under our horizon, so we’re immediately losing some of them.

For meteor showers where the radiant is much higher in our sky, we can get closer to the actual maximum zenith hourly rate. One shower with a very high maximum is the Perseids, with up to 100 meteors an hour when it peaks in August. That does vary year by year, but the Perseids is generally a good meteor shower. The July Gamma Draconids are also very high in the sky, but their maximum zenith hourly rate is just five. We might get close to that if we move forward to the 28th, the date of their peak. Their zenith hourly rate does go up to four while the radiant is over our horizon, but it doesn’t quite make it to five for us, and because of the brightness of the sky, we’re still not getting to see all of the meteors that that radiant is producing. Moving down lower in the sky, we can see a few other showers that are peaking on the 30th, when the Moon is in the sky, which is going to affect our view. The Alpha Capricornids are producing up to about four, with us getting about one of them. The Piscis Austrinids have already peaked, but our local hourly rate for those is going to be quite low because of how low they are in the sky.

The Southern Delta Aquariids are the main shower of the month. They’ve got a maximum zenith hourly rate of about 25, and when they are up for Ireland they’re at about 23. However, we’re only actually seeing about three an hour from this meteor shower, partly because it’s so low in the sky and partly because of how bright our sky is. Of course the best place to see a meteor shower is out in the countryside, so we will remove the light pollution to give ourselves the ideal view. The amount of meteors from the Southern Delta Aquariids goes up to nine an hour, which still isn’t very high. We’re getting about two an hour from the Alpha Capricornids at the same time and we’re seeing about 2 from the antihelion point. The other meteor showers whose radiants are up are are either before their peak, like the Eta Eridanids and the Perseids, or they’re after their peak like the July Gamma Draconids. Despite being past its possible peak of five on the 28th, it’s still providing three on the 30th. The current zenith hourly rate is the amount of meteors predicted for a given time coming from that meteor shower if it was at the zenith. For the July Gamma Draconids, their rate is three and we’re actually seeing all three of them when we’re in the countryside. All three an hour, which isn’t a lot, but these do all add up. All together, there’s sixteen meteors an hour from the combination of these multiple meteor showers.

That of course, pales in comparison to the hundred meteors we can get from a shower like the Perseids alone, but of course, we’re not in the best place to see this. The Southern Delta Aquariids are very low in our sky and it doesn’t look like we’re seeing them at the actual peak of the meteor shower. If we get rid of the atmosphere and the ground, that would let us see many more meteor, but it’s not really something we can achieve in real life. We will do it in Stellarium and follow the radiant under the horizon, waiting until we’re up to the actual max. Once the rate predicted for this time and date is at its maximum of 25, it is under the horizon, not directly under our north, just under the northwest. That means we want to move towards the east, towards the other side, the other hemisphere of the planet, to try and get this above the horizon.

This meteor shower will be at its peak and above the horizon in the Pacific, at least in Japan. We’ll go over to the Pacific coast of North America, where the view still good, but not ideal. Pretty close to Hawaii would be the more ideal location. It’s not quite at the zenith in the sky, but it is still much better. There are other islands lower down in the Pacific closer to the equator that probably would give us an even better view. From near the equator the zenith hourly max is 25, it will be at 25 at this time and the local hourly rate is 25. Even with the ground and the atmosphere it looks like we have found just about the perfect location to see this meteor shower. Of course, further south, a little further north, it would still be really good. We’re not exactly at the equator, we’re a little below it, so it is a little off of the exact zenith and it’s still perfect. This shower is in the constellation of Aquarius, which is on the ecliptic. The closer we are to the equator, the closer that is to the middle of the sky. It looks like we found the perfect place for it, right in the middle of the ocean inconveniently enough.

Let’s see what kind of rate we would be getting if we go to a location that probably has a few more people. On the coast of North America, around California, it’s still 13, much better than the nine that we were getting here in Ireland. As the meteor shower gets higher in the sky, we get more, getting up to 17 which is pretty good. That is another very good location to see this meteor shower. We’re getting 17 meters an hour just from the Southern Delta Aquariids. We’re getting another one from the July Gamma Draconids, so that’s 18, up to 21 once we add in the Alpha Capricornids and the Piscis Austrinids add another one, so up to 22. 22 meters an hour, a little bit better than what we would be getting here in Ireland on the same night. Partly because California is closer to the equator, but also because it’s closer to the actual peak of the meteor shower when itis up, which can make a very big difference. Some meteor showers, their peaks are quite diffuse, they’re quite spread out, the peak can last over the course of several days in some cases. Other meteor showers however, the stream of material that produces them is much more narrow, so we end up seeing those meteors for really brief windows, they peak right on their peak and disappear very quickly afterwards. Different meteor showers behave a little bit differently.

We’ve gone to the other end of the Pacific, now we’re pretty much in Japan and we’re again getting 15 meters an hour just out of the Southern Delta Aquariids, so we’re probably up to about 20 all tolled, and this is still reasonably dark. Of course if you were in the city you would see less. We’ll move down, we’ll remain on the Pacific but we’ll move down into the southern hemisphere which will put the meteor shower nice and high in the sky. If we went too far south it would put the meteor shower down on the other side of the sky, down in the north rather than us seeing it low in the south. We’ll stop at the Southern coast of Australia. From there we’re getting 23 out of 24 which is pretty good. That is another brilliant place to see this meteor shower. We will get some meteors here in Ireland but there will be a much better showing from other locations. The Piscis Austrinids are much higher in the sky as well. If we come back to the 28th, Australia doesn’t quite see the peak, only getting three out of five going up to four as the meteor shower goes down. The Piscis Austrinids and indeed Australia have names descended from an old word Latin for the south, austral. Of course the Piscis Austrinids are going to look a little bit better from Australia, and indeed the southern hemisphere in general, than they do here in Ireland.

Those are the meteor showers at the end of the month and some of the places where they will look best. Of course we will see some extra meteors in the sky no matter where we are in the world on the 28th and the 30th with so many different meteor showers peaking, even if their peaks are pretty low. I hope you enjoyed this little trip around the world to a few different views of the meteor showers. If you did enjoy this piece, 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 watching and hopefully I’ll see you back here next time.