Caoimhín's Content

Today we will continue to look at the November sky. We are now into November and we’re going to start by taking a look at the sky on the 5th of November. Just as the Sun sets, the radiants of the first meteor showers of the month will already be up. Low in the east we have the Northern Taurids, their radiant is right next to the Moon early in the month. The Southern Taurids a little bit further east, with the antihelion point between them. We do also have the Andromedids, which are peaking on the 5th of November. Their radiant is nice and high in Andromeda. The Andromedids have a Zenith Hourly Max of 3, and they are producing that at 8 o’clock on the 5th, right at their peak. We’re only seeing about one an hour given that we’re viewing from the city and also the bright light of the Moon is going to interfere. That will be true for the Northern Taurids as well.

The Northern Taurids, are peaking on the 12th of November, while the Southern Taurids peaked back on the 10th of October. These are two different meteor showers which both have the Comet 2P/Encke as their parent body. There’s a good chance that the comet broke apart in its past and that one of these meteor showers is actually from the comet itself, whereas the other, the Northern Taurids, are really from the part of the comet that broke off. This is identified as an asteroid, but it follows the same orbit as the comet, making it practically just a different part of the comet stream. The stream of the comet is the long tail that it leaves behind, not just the tail that we see in the sky, but the stream of matter that it leaves behind as it moves through the solar system. Moving forward to the 12th, the Northern Taurids are up to their zenith hourly max of 5, we’re seeing four from here in Ireland or we will be on the 12th, and with the light pollution and everything, it’s cut down to just the one again. These meteor showers, are quite small, both the Andromedids peaking right at the start of November and then the Northern Taurids coming a little bit later.

We’re going to have to move a bit closer to morning time for the radiant of the Leonids to come up. The Leonids are the better shower this month, and peaking much later. Moving through to morning time means crossing over to the 13th, and the radiant of the Leonids is also quite close to the Moon. Thankfully the peak of the Leonids is coming much later in the month, not until the 17th of November. If we keep moving forward to the 17th, it will show a variable range from 5 to 20. This year it looks likely that the Leonids will be in the 15 to 20 range, but this is the meteor shower that produces hundreds of thousands of meteors when it’s really, really at its peak. This year the Leonids are peaking really just at the start of the evening of the 17th.

For Ireland, this is when the Leonid radiant is way out of view for us, so we’re not going to see many of the Leonids when they’re at their highest, simply because the radiant isn’t above the horizon. We can still see meteors when the radiant isn’t above the horizon, but we’re going to see less of them the further from the zenith the radiant is just because so many of them will be appearing under the horizon for us. Coming closer to the 18th the rate is still 4 to 16 as the radiant comes up. If we hop back to just after midnight into the 17th, after sunset on the 16th, the rate is just 3 to 10. The Leonids, aren’t going to be as amazing this year, as they are on other years, but we will be able to see a reasonable amount of them after sunset on the 17th. We will in Ireland probably see more later as we come through to the 18th, but if you’re in a different location where the Leonids are going to be up closer to their peak where they’re under the horizon for us, then you might be in with a better shot.

The parent body of the Leonids is Comet 55P/Temple-Tuttle. Due to the way that this comet goes around the solar system when it passes near the Earth, which it does every 33 years or so, it leaves behind a fair bit of material. Roughly every 33 years the Leonids will have a major shower, a much, much bigger shower than normal. This isn’t usually the exact same year as the return of the comet, but a bit later. That’s when the amount of meteors can get into the hundreds and thousands. These are meteor storms,as they’re called, not just meteor showers. This year looks like it’s just going to be a normal meteor shower year. The Leonids are are also very fast meteors. They have a geocentric meteoric velocity of 71 km/s. That means from our perspective, as if we weren’t also moving, they’re traveling at us at 71 km a second. If we hop back to the Northern Taurids, they’re velocity is just 29 kilometers a second, and the Southern Taurids are similar, just 27 kilometers per second. The comet that gave rise to the the Taurids, 2P/Encke, is going around the solar system in the normal prograde way, they’re essentially moving the same direction as us. Furthermore, it is a short period comet, so it is moving slower anyway. With the Leonids, their comet, 55P/Temple-Tuttle, is a retrograde comet, so it’s going around the solar system essentially backwards compared to everything else. That means those meteors are really coming at us. We’re not just catching up to them and pulling them in with our gravity, they’re streaming right at us, so those meteors end up being much faster, and you may be able to see that as they streak across the sky.

We’re after going through a fair portion of the month here, from the 5th to the 18th, just looking at the meteor showers as they would be from the city. We’re going to come all the way back to the start of the month and head out to the countryside to review the stars. Of course, for the early part of the month, the light of the Moon is going to interfere, so it’s going to interfere with the meteor showers, you will see fewer meteors due to the Full Moon.

If we come back towards sunset at the beginning of the month, you can still see the summer triangle, it hasn’t completely left our sky yet, but it isn’t going to be in the sky for a large portion of the night. Saturn is still with us pretty much for the entire night, although it will be gone by morning. We’re still losing some of those constellations lie Sagittarius in the southwest. The Pleiades are already above the horizon at sunset and as we move later in the month, once the Moon is out of the way, we can see the Hyades as well. Essentially all of Taurus is already up just after sunset, at about 6:45. We can still see part of the Milky Way, but it is mostly this outer arm section tailing off towards the edge of the galaxy, we’re seeing way less of the core of the galaxy. We don’t even have to go all the way through to morning time for the wintertime constellations. At just 11 o’clock we’ve got Orion, Gemini, the start of Leo with the Leonid radiant, and Auriga with that bright star Capella. They’re all up reasonably early in the night, at just 11 o’clock.

They will be up reasonably early in the night once we get a little bit later in the month. As we start pushing towards morning time, Arcturus will come up, and that means the constellation of Böötes or Boötes, is up as well. The Plough is pointing down to Arcturus as it normally does, which indicates that we’re going to start seeing more of Virgo in the morning. Pushing right up to sunrise, and there is Spica in the morning right next to Corvus, just as we come around to morning time on the 20th of November. Once we’re a little bit later in the month, we’re still just about seeing Venus but as you can see, it’s incredibly close to the horizon. Jupiter is a much, much easier bet and as I mentioned previously, we’re losing Venus entirely once we come through to the end of the month, but we are gaining Mercury in the morning.

Mercury will be coming up just as we go from November into December, but even the highest Mercury reaches above the horizon is still really low and that’s going to keep it reasonably difficult to see. It is getting into winter, so we are seeing things at a slightly different angle. Even during the day, and even in early November, the Sun is incredibly low in the sky for midday here in Ireland. If we come back a little bit to the beginning of November, back to the 6th, the Sun is incredibly low in the sky at midday. We’re really coming into winter, and that’s giving us, of course, much longer nights, but it also means objects that are close to the ecliptic will get higher at midnight. This means, objects like Saturn and like the Moon, especially when they’re up close to midnight, so our Full Moon in November, for example, they’re going to be really high in the sky, and that should make them even easier to see.

For example, with Jupiter, even at 5 o’clock in the morning, Jupiter is about as high in the sky as it can get. If we take a closer look, its magnitude -2.36, it is an incredibly bright object. We’ll see it at -2.21 because it’s reduced by 1.16 air masses. This isn’t much of a different and that’s because Jupiter is so high in the sky. If we come down here and look at Venus instead, we can see that Venus is brighter, magnitude -3.92, but it’s reduced to almost the same brightness, -2.36, by 12.04 air masses. This is because it’s so much lower in the sky. Venus and Jupiter will appear to be a comparable brightness, but that’s only because they’re getting extincted by such different amounts of atmosphere. That’s going to be a very big difference for those of us here in Ireland, how you see it where you are will vary, of course. We’ll make a more direct comparison with Jupiter just to finish up. We’ll bring Jupiter back down towards the horizon, nearly where Venus was. It’s still magnitude -2.36, but now it’s reduced to just -1.65 by 5.51 air masses because it’s so much lower. In fact, we can get that up to 12 air masses if we get it right down to exactly where Venus was. That reduces it to just -0.74, so not even as bright as some of the brightest stars that we can see in the sky.

That is just a quick look ahead to some of the other things that are coming up in November, the positions of some of the constellations, and a quick touch on those meteor showers. I will get back to the Leonids once we’re closer to their peak at the end of the month. I hope you enjoyed this piece, if you did then please do like like it. If you like this kind of content, then please subscribe to this YouTube channel. Thank you very much for reading and hopefully I’ll see you back here next time.