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Today we are going to look just a little further ahead into April to take a look at the Lyrid meteor shower. The Lyrid with meteor shower is going to be peaking pretty late in April, the 22nd/23rd, so we’re going to have to push pretty late to get to the peak. The Lyrids do run over the course of April, starting in mid-April, on the 13th and finishing on the 30th, but its maximum will be on the 22nd. Stellarium provides a prediction of how many meteors will be visible, but these predictions won’t necessarily be accurate.

Looking at the night of the 22nd, Stellarium shows a zenith hourly rate of 75, with a local rate of 23. This is partly because we’re basing this on a simulated view from the city with a limiting magnitude there of 5.7. Seeing things from a city like Cork city, any object fainter than magnitude 5.7 will be blocked out, and that includes any fainter meteors. Pushing later in the night, it goes up into the thirties. This is of course only a prediction for how many meteors we’re going to see, but it is a promising one. The rate gets higher, or at least the amount that we’re going to see seems to be getting higher, as we get closer to morning time. The Lyrids are a pretty variable shower and that’s partly because of their parent body, the comet C/1861 G1 Thatcher. As you can see can see, it starts with a C for comet, rather than P for periodical, but this is considered to be a periodical comet. It’s just that its period is very very long, roughly 422 years. That means the trail of dust that generates the April Lyrids, doesn’t get replenished very often. However, we do see plenty of meteors coming from this shower, usually ratings around the 20s are what get reported, and those numbers could potentially be lowered due to the effect of light pollution.

Without any light pollution, of course you’d see more of these meteors. If you are in the countryside, the number get significantly better, potentially predicting up to 49. With a variable meteor shower, a range is often shown, and the upper limits are in the 70s and the 90s, but those are uncommonly high. Based on the records of the past few years, getting quite that high isn’t very likely, we’re likely to see a zenith hourly rate somewhere in the 20s, which is pretty good. Even better, in the April Lyrids there are occasional April fireballs, or Lyrid fireballs. You may occasionally get very bright bolide meteors, also known as fireballs, from the April Lyrids.

Continuing forward puts us in the morning of the 23rd, because we started on the night of the 22nd. This brings us past the peak, so instead let’s go back to the morning of the 22nd. This gives us potentially very high local rates in the 70s. Dates unfortunately, run from midnight to midnight. I guess it does make sense that dates normally run from midnight to midnight, but it means that there is a break in the middle of the night where we change from one date to the other. We can see this by looking at the Lyrids on the 21st. This is the day before the peak, but as we cross midnight we transition into the 22nd, bringing us to the date of the peak. As we come to the date of the peak, the amount of meteors we’re seeing starts climbing up into the 60s and 70s. Due to the dates we use being suited to our daytime lives, sometimes a peak on the 22nd is sometimes seen just after midnight on the 21st, other times just after sunset on the 22nd. In some situations, astronomers measure from midday to midday instead, to prevent any confusion.

As such, with local rates maxing out at 71 in the countryside, the actual peak for us in Ireland may be the morning of the 22nd. Of course, an actual rate closer to 30 or 40 is still more likely than 71, and the glow of sunrise will begin to block them out. That is at least what this software is predicting. The local rate starts tailing way down as the Sun rises, while to over all rate gets up to about the 80s, while it was out of view during our day. This suggest that from here in Ireland we’re kind of catching beginning and the end of the shower, where as the real peak of the shower, by the predictions of this software, seems to be happening on the other side of the planet.

The April Lyrids, like all meteor showers, come from a stream of material left behind by a comet which comes around very rarely. Thankfully, there is enough material in that stream that we get a good amount of meteors regularly, each year, and some of those meteors are incredibly bright fireballs. When this comet eventually comes back around, it should replenish that stream of material, but that’s not going to happen for quite a long time, not until 2283. It is quite far in the future that this comet will come back around, however there is something else that happens to improve the shower. The stream of material causing this shower stretches through the Solar System. The comets that have these incredible long periods that are hundreds and hundreds of years, they are usually the comets that get pretty far from the Sun. These comets essentially move through the whole solar system. The path of the comet is very long, as is the stream of dust on that path. The position of the other planets in our solar system have an effect on this trail of dust. As the other planets move around they push and pull the trail of dust, the same trail dust we move through in April every year. This leads to a cycle. About every 60-years or so, the Lyrids get way way bigger, you get a very intense Lyrid meteor shower. This is roughly every 60 years, so the next one should be coming up in 2042, not this year unfortunately.

Even so, we should still end up getting a good number of meteors this year, all through the night. We should get some on the actual night of the 22nd, but particularly closer to morning time the day before the peak. If you go out on the evening of the 21st and wait until into the morning of the 22nd then you should get a lot of meteors as well. You can tell from the name that they’re radiating from up in the constellation of Lyra, their radiant is at the western edge of the constellation, off to the side of the star Vega. That’s where the meteors are radiating from, essentially the Earth is moving through the trail of material in roughly that direction. This material is certainly rock and dust, as some of these meteors leave behind trails of debris. With actual material left behind, this stream is definitely composed of rocky material, not just little flecks or dust particles, these are little chunks of rock. Of course they need to be quite big for them to be fireballs and for them to leave long persistent trails. Even though they are few in number they can be quite good meteors.

Though the radiant is in Lyra, this doesn’t have too much of an effect. Even if the radiant is below the horizon we can see meteors from it. They radiate from the radiant, but they can appear almost anywhere in the sky. Even when the radiant is really low in the sky there, we can see meteors way across the sky, much further to the south or to the west. However, their trail would trace back to this radiant point where they radiate from. If you are paying close attention, especially later in the night, a little bit after midnight, the radiant is nice and high in the sky, you may see meteors going the wrong way. Meteors may be seen crossing the sky, going across the path of the Lyrids, or even going towards Lyra. Of course that means they can’t be radiating from Lyra if they’re going towards it. Those then are likely meteors from the antihelion point instead, just normal background meteors that would happen without the shower.

On the correct dates, on the dates that are going to be good, the Moon is nowhere to be seen. If we move forward towards morning time, the Moon comes up very early in the morning with Venus. It isn’t a particularly prominent Moon either, the Moon probably wouldn’t be bright enough to block out the Glow of Milky Way. However it’s not going to be up while the sky is dark enough, the glow of the Sun will block out the Milky Way as the Moon is coming up anyway. Most importantly, the Moon isn’t going to be in the way over the course of this meteor shower which makes things even better, especially if you are in the city because in the city we’re already suffering from light pollution. The light of the Moon would block out anything that’s left after light pollution if it was full enough. This is especially true when it comes to meteors. The Lyrids can thankfully be very bright, so they can shine out if they are fireballs, but you will miss all of the fainter ones. Then again the bright fireballs are often the most exciting part of the shower, so maybe you won’t find like you’re missing too much.

By late April we can tell, by virtue of the radiant of the April Lyrids being up, that Vega is already up as the Sun is setting. This doesn’t mean the summer triangle is up as the Sun is setting, the summer triangle isn’t even fully up by the time the sky is dark. However, part of the summer triangle is with us all night long, and not just in a circumpolar way, it’s actually with us from sunset to sunrise. We can see all of the triangle in morning, so it’s just another sign that we are moving closer and closer to summertime. By the morning you may also see the radiant of the Eta Aquarids. The Eta Aquarids are radiating from pretty close to the Sun and they’re not actually going to peak until May. We’re still going to have to wait a while to get a good amount of meteors from those.

That’s the April Lyrids, they are coming up and they are a good meteor shower. In the case of the Lyrids it may be quality rather than quantity, we may not get a lot of meteors but there is a chance to get some of those really impressive fireballs. I do hope that you do get to see some of those, I also hope that you enjoyed this piece, if you did please do like it. You can also subscribe to this website and my YouTube channel if you’d like to see more of this content. Thank you very much for reading and hopefully I’ll see you back here next time.