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Today, we are going to take a quick look at a few different meteor showers, beginning with the meteor showers that are peaking at the moment in late July. Then we’ll take a look ahead to the meteor shower that will be peaking once we come into August.

We’re starting with sunset on the 28th of July, but we’ll need to move a little bit later for the radiants of all of the meteor showers to come up. By just a little after midnight, all of the radiants we’re interested in will be above the horizon from Ireland. Most of them are low to the south, though a couple a re a little higher in the sky. Using Stellarium, if we click on them we’ll be able to see the dates at which they’re peaking. Starting low in the south, the Piscis Austrinids in the constellation of Pisces Austrinus, the Southern Fish, that’s peaking on the 28th of July. It’s Zenith Hourly Rate is just 5 at maximum, and we won’t even be seeing that many of them, because the radiant is so low in the sky and because we’re viewing them initially from here in a city. Moving up a little to the Southern Delta Aquariids, they provide a few more meteors, their maximum is on the 30th of July, when we’ll be seeing a ZHR of 20-25. If we move through a couple of days we’ll see those numbers change. We’re already through to the 29th, having passed midnight on the 28th, so we’re already pretty close to the peak numbers, but they do go up as we move through to the 30th and then back down again as we move through to the 31st.

For different meteor showers, the times at which they peak have a different influence on how many meteors we’re going to see around the peak. Some meteor showers have a very narrow peak, so we really only see their maximum on the day that they’re peaking and we see very little, or none at all, on the dates around their peak. For other meteor showers, we’re going to see a slightly wider range, so even though they’re only at their maximum during their peak, we can still see quite a few on the days either side, for example, the Southern Delta Aquariids. If we take a look at the Alpha Capricornids, we can see they’re also peaking on the 30th of July, with a maximum Zenith Hourly Rate of 5. We’re seeing 3 on the 29th, going up to the expected 5 once we move through to the 30th and then back down to 4 once we move through to the 31st. We are looking at all of these times just a little bit after midnight, so it’s really better to say early on the morning of the 29th. If you wait until midnight on the 29th then you’re going to be seeing these things as we move into the 30th. Moving from the Alpha Capricornids way up to the much higher July Gamma Draconids, we can see that they’re also peaking on the 28th, also with a Zenith Hourly Rate of 5.

We can see that these meteor showers are all peaking around the end of July, but most of them have pretty low maximum Zenith Hourly Rates. Two are peaking on the 28th, so we’ll come back to the actual 28th at 2 o’clock in the morning, just as it becomes the 28th. The Piscis Austrinids are peaking at 5, the July Gamma Draconids are producing 5, and the antihelion point is producing about 5 as well. All these different meteor showers are all contributing to the amount of meteors that we’re seeing in the sky. The antihelion is part of the default background rate, which is normally about 10. We’ll start with the Zenith Hourly Rate of 10 and then add on 5 and 5, bringing us up to 20.

We can alter than in Stellarium, which defaults to the normal rate of 10. We can increase that to 20 with ease. That’s a standard Orionids rate, a standard rate for a reasonably small shower, and we’re looking at multiple very small showers here. If we pull back and take a look at the whole sky, we would still have to wait quite a bit of time to see any meteors passing the sky. If we see 20 meters an hour passing the zenith and there’s 60 minutes in an hour, then it’s going to take about 3 minutes before we see one meteor crossing the zenith. These things are of course a little bit better if we take away the light pollution. If you move through time in Stellarium faster than the normal rate of one second per second, then you won’t see any meteors. Even though you’d expect the number of meteors we’d see to increase because we’re moving through time at a higher rate so we should see more meteors, when we move through time at those elevated rates, we actually don’t see any meteors, the meteors just sort of stop. This is purely due to the software, and of course a sped up sky full of meteors would be quite cluttered. Looking at the sky with a ZHR of 20, we’re not even seeing any meteors in a truly dark sky in a short period of time. We would see a few if we waited long enough, a few would pop up, but it would be close to one every few minutes,

By moving later, up to 2 o’clock, we’re after bringing the radiant of another meteor shower into view, the Eta Eradinids, they’re peaking on the 7th of August. If we go and click on the Perseids, they are peaking on the 12th of August, so there’s a couple of meteor showers coming up in the early part of August as well. Most importantly, the Perseids’s Zenith Hourly Rate is roughly 100. We’re a couple of weeks or before their peak, so of course we’re seeing no meteors really from them in late July, even though their activity does run from the middle of July through to the end of August. With these meteor showers that have very long ranges of activity, we’re really not going to see many at all far outside of the day of their peak, or, as I mentioned with meteor showers like the Southern Delta Aquariids, for more than a few days either side of their peak. We can see with the Eta Eradinids here, they’re not producing very many meteors either, a ZHR of just 3, and there aren’t other meteor showers peaking at the same time as them to help.

While we have the Piscis Austrinids and the July Gamma Draconids all peaking at the same time, neither of them are particularly big, but at least they’re peaking at the same time, so at least we’re getting a contribution from all of them. This peak has passed, but it will come again next year. If we move a couple of days forward to the 30th, we’ll come to the peak of two more showers. The Alpha Capricornids are giving the 5 that we’d expect their maximum to be and we’ll say that the Southern Delta Aquariids are giving 25. That would be 30 on top of the 10 that we already have, which would bring us up to 40. With 40 meteors an hour and taking a look at the sky from the countryside with no light pollution at all, we should start seeing some meteors, but again, we’re only going to see one every minute or so. With 40 meters an hour and 60 minutes in an hour, we’re not quite going to see a meteor every minute, more like every minute and a half on average.

With rates like that, it would take a while for the meteors to come through in the sky and of course I don’t want to just sit staring at a screen for minutes and minutes waiting for the meteors to come up in Stellarium. That certainly wouldn’t make the attached video particularly exciting. However, I wanted to be clear about the rates that we’re going to get. There is some excitement about the meteor showers that are peaking in late July, and there is a lot of them. There are four meteor showers peaking in late July, which is quite a few. We’ve got the Pisces Austrinids and the Alpha Capricornids peaking on the same date, the 28th. Their peak has just passed but even around the 29th, we should still see some meteors from them. The Southern Delta Aquariids and the July Gamma Draconids, they’re peaking on the 30th, so we still have them to look forward to. However, with maybe a meteor every minute and a half in a dark sky, fewer of course in the city, they aren’t the most productive showers, even all occurring together.

If we move forward to the 7th of August, and of course we are coming pretty close to August now, we can see that some of the meteor showers, the July Gamma Draconids for example, disappear. This is because we’re out of their range of activity. New meteor showers have popped up as well of course. For the Eta Eradinids, the Zenith Hourly Rate of 3 won’t be too exciting. The Kappa Cygnids are also coming up, but they’re not peaking until the 18th of August, and the Northern Iota Aquariids are not peaking until the 21st.

We’ll only push forward to the 12th for the Perseids. The Moon will be there, which is unfortunate, the extra light of the Moon is going to limit the amount of meteors that we see in the sky. We’re seeing a rate of 72, and we’re just starting the 12th if we’re looking at an early morning sky. If we move forward to just after midnight, into the 13th, Perseids rate is higher. Looking later on the 12th, or even a little after the 12th, is when we’re going to see them closer to their peak, rather than the beginning of the 12th. Let’s just say that they’re contributing their high rate of 100, we’ll imagine that they’re doing the absolute max that they could, even though that’s not guaranteed. That gives us 110, 100 on top of the base rate of 10, and that’s the standard Perseids rate according to Stellarium. If we take another look at the sky, hopefully we will get a meteor coming through. In Stellarium, the meteor shower radiants are still in the sky, which will clog things up, but we can get those out of the way. The stars shouldn’t clog things up too much because of course they’re fixed points in the sky, it’s not too hard to tell the difference between a meteor flying through the sky and a fixed point like a star, but just to be safe, we can remove them in Stellarium as well.

We’re looking here at a night sky in the countryside, even with no stars we can still see the glow of the Milky Way, and Uranus is being suggested as a tiny little dot. We’re looking at a sky for a standard Perseid rate of 110, which is potentially a little higher than you might actually see, especially if you’re suffering with things like light pollution. Unfortunately, we do have the Moon there, which is the realistic state of affairs for this year, that’s where the phase of the Moon will be. We should be seeing more than one meteor a minute passing the zenith, almost every 30 seconds. We should be seeing a couple of meteors a minute, if we’re getting a hundred an hour, and there’s only 60 minutes in an hour. Some of them are going to be faint, some of them are going to be difficult to see. We can go even further in Stellarium, ,we’ll get rid of the atmosphere and we will get rid of the Moon, even though that brings us to the wrong date. The meteor rate of Stellarium will stay at 110, regardless of any actual meteor showers peaking. This lets us look at the sky almost as dark as it could possibly be. This gives a view darker than it could ever actually be in real life, because in real life we have the stars. We’re still looking at a standard Perseid rate of 110 even though it’s completely the wrong day, to get the Moon out of the sky. Unfortunately, other than maybe seeing a faint meteor, I’m just not seeing any in Stellarium. Maybe I’ve missed one, hopefully I’ve missed one, maybe you’ll see more if you take a look at the attached video yourself.

Hopefully we will see more meteors in the real sky than I did in simulation, but I wanted to give a realistic comparison between the number of meteors that we’re going to see at the end of July and the amount of meteors that we’re going to see in mid August. That’s not to say that you shouldn’t go looking for the meteors in late July, we’ll just have a better chance of seeing meteors in August than we would in late July. I hope that you enjoyed this piece, if you did then please do like it and if you enjoy this kind of content, then you can subscribe to this website and my YouTube channel. Thank you very much for watching and hopefully I’ll see you back here next time.