Caoimhín's Content

Today we are looking into the past, just a couple of days back to the 29th of June. This was the last Full Moon. We do, of course, have another Full Moon coming up at the end of July, but this was the most recent Full Moon that we had. In Ireland we saw it at 99.8% full and a bit over 404,000 kilometers away from us once it was reasonably high in the sky. If we move earlier in the evening, that number goes down. We’re not seeing it at its absolute fullest, of course, but we are edging towards 405,000km as we go back towards moonrise. A Micromoon, the smallest Full Moon that we can see, is by some definitions (the definition that I’m going to use here), when the center of the Full Moon is over 405,000 kilometers away from us. Although this still a bit under 405,000 km away, Stellarium isn’t measuring our distance to the center of the Moon. As far as I know, the distance it shows is to the surface of the Moon rather than the center. If we add on the radius of the Moon, which is about 1,700 kilometers, that comfortably brings us up to 405,000 kilometers.

If we keep pushing back, eventually the Moon will go under the horizon for us here in Ireland, because. However, even without putting the Moon under our horizon, just as the Moon rose at 99.8% full, it was 405,000 kilometers and a bit away from us. Granted, this is when it was very low in the sky and out of view for some people. The Moon was over 405,000km away, so it was a Micromoon. That’s the last Micromoon that we’re going to have in 2026. We’re going to get rid of the ground and the atmosphere and we’re going to start moving forward, through to the next Full Moon that is still upcoming at the end of July. On our way, we’re going to get the New Moon. The July New Moon is only 360,000 kilometers away from us, closer than the Full Moon, for now. Forward to the next Full Moon, 99.9% from here in Ireland, so even better, and we’re seeing it at 398,000 kilometers. That’s almost 10,000 kilometers closer to us than the last Full Moon, and that trend is going to continue. We’ll go all the way through July into August, and it’s down to 389,000 kilometers. We’ll go through again to September and it’s 375,000, to October, 365,000, roughly another 10,000 kilometers so that’s nice and regular. It’s going to keep coming down.

Here we are through to November, and it’s only 357,000 kilometers away from us. This counts as a Supermoon. By the definition that I am using, anytime the Moon is closer to us than 360,000 km, it is a Supermoon. Again, that’s measured to the center of the Moon, so we are under it here, but if we added on the radius of the Moon, that would make us almost 2,000 kilometers further. The radius of the Moon again, about 1,700 kilometers. We’ll keep going all the way through to December, because the trend continues. It gets down to 351,000 kilometers away, almost 10,000 kilometers closer to us than the limit of the definition. Its 45,000 kilometers closer to us than the Micromoon that we just saw in June. We’re going to move forward again, because I did hear that the First Full moon of 2027 would also be a Micromoon. It is, 352,000 kilometers away, just a teensy-tiny bit further from us than the 351,000 kilometers that we’re getting in December. We just saw our Micromoon and we will, at the end of the year, get our Supermoons. Bringing back the atmosphere in the ground, everything should still be fine, everything should still be above the horizon.

If we bring the Moon back to just about when it’s rising, the Moon still looks pretty small, and the Moon is a lot smaller than it looks. When we see the Moon in the sky, it appears much larger than it actually is, there’s a bit of an optical illusion going on. This is exaggerated when the Moon is closer to the ground. However, I do think I have a way around this issue, which is to actually perform a measurement. Unfortunately, that’s really what you need to do to tell the difference between a Supermoon and a Micromoon. The difference in apparent size is only about 12 to 14%, which is pretty small, and we are hopefully going to see just how small, assuming that I can be accurate enough to make this work. Stellarium does provide an angle measure tool which is going to tell me how many degrees of arc the Moon is taking up in the sky. I’ll try to be as level as I can and as close to being directly across the equator as I can. That gives me 33 minutes of arc and change. We’re now going to go back to the Micromoon to compare. The December Supermoon is the Superest Moon that we’re going to get this year and the Superest Moon of the next set of Supermoons. As I mentioned, we’re going to go through several Supermoons, several Full Moons that count as Supermoons November is going to count as a Supermoon, January is going to count as a Supermoon in 2027, but the December Supermoon is going to be the biggest Supermoon, the closest of the Supermoons.

On our way back, we pass the New Moon blocking out the Sun on the 12th of of August. We’re going to have a partial solar eclipse from here in Ireland, a total solar eclipse from Iceland and Spain. Following the Moon from December to June, we pass this solar eclipse coming up at the end of this year with the New Moon almost in front of the Sun. We’ll keep coming back to last month. Back to the 29th, that is our Full Micromoon. We’ll turn back on the atmosphere and the ground and we’ll move forward until the Moon is above the horizon. Technically this is a little unfair, the Moon’s cycle is 29 and a half days and even that isn’t perfectly accurate, 29 and a half days roughly. That makes it hard to catch the Moon at the exact opposite part of its cycle, as it will be over a different part of the Earth. However, its better to get the Moon far enough above the horizon that the atmosphere isn’t distorting it into some sort of oblique shape.

I’m going to try measure as close to directly across the equator as I can, and its 29 minutes and change of arc. A difference of almost 4 arcminutes, but 4 minutes of arc isn’t a lot.. I will try to be just a little bit more accurate, but its still 29 and a half degrees. It is an exercise in futility. I will never be as accurate as true measurements, mechanical measurements, the kind of analysis that a computer can do, measuring where the brightness begins or where the contrast is. I’ll never be as accurate as astronomical systems but even here, just looking at it roughly and possibly making mistakes, we’ve got a different size of Moon. So the Supermoon is coming up, the Micromoon, the Microest Moon that we’re going to get this year has just passed by. So I hope that you got to see it, but of course the Micromoon is smaller and a little fainter. It’s only a tiny bit fainter, it’s very hard to tell how much fainter, and it’s hard to tell how much smaller. Regardless, it is past, from here the Moons are getting bigger and we will get our biggest just at the end of the year in December.

So that’s the Supermoon and the Micromoon. I am personally a little glad that newspapers have started talking about Micromoons. Newspapers were making a big deal about Supermoons for years and I was a little apprehensive because the difference is only about 12%, not many people would notice it. However, people do seem to like the Supermoon. The idea of a Supermoon is a popular thing, people want to see it and want to know more about it. People, and by people I mean newspapers, newspapers and websites, have started mentioning the upcoming Micromoons and when the Micromoon is occurring and I think that’s good to make sure that people know the Supermoon and the Micromoon are two different ways the Moon can look. The Moon can look bigger and so of course it can also look smaller and that provides an opportunity to explain the actual details.

I hope you enjoyed the quick comparison made here and I hope you’re looking forward to the Supermoons coming up. If you enjoyed 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 reading and hopefully I’ll see you back here next time.