Caoimhín's Content

Today we are going to take a look at an eclipse. Of course, we have a very exciting annular eclipse coming up on the 17th of February visible from Antarctica, and we have a total solar eclipse coming up later this year visible roughly from Europe. Iceland and Spain will be the two main landfalls of the totality of the eclipse, but a partial will be visible even in Ireland. For this eclipse we’re going down to the southern hemisphere, aiming roughly for Timor, which is an island off the coast of Australia, near New Guinea.

Just to explain some potential inconsistency in the terminology I use, Timor is an island. West Timor is part of Indonesia, and East Timor or Timor Leste is a separate country. Similarly, New Guinea is an island whose western part is Indonesia, but the eastern part of Papua New Guinea is a separate country. The eclipse was visible all over the island of Timor, and all of TImor Leste, but not for all of the nation of Indonesia. The eclipse totality was only visible from the Indonesian portion of New Guinea, with only a partial visible from Papua. I apologize for any mix-ups. Furthermore, Timor means “east”, so Timor Leste is “East-East”, which is a nice little piece of trivia.

This island of Timor saw a total solar eclipse back in 2023 on the 20th of April, so that’s when we’re going to go. We don’t have to go too far into the past here and we only have to make some slight changes to the date. We are definitely in the southern hemisphere down in Timor-Leste. With the Sun coming up into the sky for daytime on the 20th, the Moon moves in front of the Sun, making the sky dark enough to see Venus in the sky. Taking a closer look and we’re not actually getting totality, we’re a little bit off giving us just a partial eclipse. The partial is 94.7%, which is pretty good, but we are a little bit off so we’ll move a little bit further south. I do like to try and find the totality of eclipses the old fashioned way, but there are actual coordinates for totality that can be used if necessary. This time, it’s not necessary, we have perfect totality roughly from the Timor Sea.

This totality is lasted 1 minute and 15 seconds. That’s pretty normal if a bit on the short side, it’s a shorter eclipse but it isn’t far from typical. The very long eclipse of the 6 and a half minutes that we’re getting in 2027 is exceptional, and you can review some of my previous posts if you’d like to read about some other exceptional eclipses. What makes this 2023 eclipse exceptional is that it was a hybrid eclipse. From Timor-Leste, it was a total eclipse, but if we move to another area on the path of the eclipse, it will be annular. To be annular rather than partial, we need to be on the path of totality, but not at the greatest extent. Moving down to the tip of the North West Cape peninsula of Australia keeps us on the eclipse path, but not at the greatest extent. A hybrid eclipse is an eclipse that is visible as both a total eclipse and as an annular eclipse, but from slightly different locations. The path of an eclipse is very often curved, and this eclipse carved a path from the kind of southern Indian Ocean, across the edge of Australia, through Timor-Leste and up to the Bird’s Head peninsula of New Guinea.

Going south and west to Australia didn’t give an annular eclipse, so we’ll go north and east instead. The island of New Guinea is sometimes described as being a bird of paradise, with the Bird’s Head Peninsula being up on the western end, and down in the opposite direction is the tail of the bird of paradise. We’ve gone to the other side of the maximum here, which should at least give us a partial, but again not quite an annular. Due to this eclipse being a hybrid eclipse, it does have a total component, part of the eclipse is a total eclipse. Of course, that is the part of the eclipse for which exact geographical details are given, it is the best part of the eclipse. The annular portion of the eclipse, where only some of the Sun is covered by the Moon, but more importantly where the Sun is visible around the edges of the Moon, unfortunately exact locations aren’t as easy to come by for that. As such, I had to do a little bit of a hunting around, a little bit more than normal, in order to catch this eclipse in the way that I want, with its annularity rather than its totality. Hybrid eclipses are one of the rarest kinds, and when I say incredibly rare I mean just roughly 3% of eclipses are hybrid.

Off into the Pacific would be around where the eclipse finishes,where the path of totality kind of ends, so we might need to go a little bit closer to there to get annularity. Unfortunately, I didn’t go far enough, remaining too close to totality, at 99.89%, so very close to totality. The hybrid eclipses are very rare because so many things need to come together. Just like the very long eclipses that I’ve spoken about in previous pieces, where the Earth’s aphelion and the Moon’s perigee all to come together for the longer total eclipses, and of course, then the opposite for the annular eclipses. In this case, it needs to be a little bit of both, we need to be at just the right distances to get the Moon to cover the Sun with a full circle of the Moon without actually covering the entirety of the Sun, while for other locations, the Moon does cover the entirety of the Sun. To catch the annular portion, we need to go to either to the very beginning or the very end of the eclipse path.

As I mentioned, the path of the eclipse arcs up from the Southern Indian Ocean up into the Pacific. There is a little dot of land down in the southern ocean, the Kerguelen islands. Stellarium suggests the nearest location as Port-aux-Francais, East Africa, but that is on Kerguelen Island. The Kerguelen Island, there are a couple of small islands around the also small main island of Kerguelen, is part of France. To what degree I won’t get into because, of course, these things can be complicated. A rough guess did bring me very close here to where annularity should be occurring, so I should be able to get the exact location just by changing the latitude and longitude. I went with changing minutes of arc rather than seconds of arc, as otherwise it could take too long. This caused the amount of the eclipse to change, but it very slowly. Full degrees are large jumps over the earth’s surface area, so they make a big difference pretty much immediately to how much of the Sun is covered. It took a while to definitely get closer, it hard to get this one exactly right.

After quite a bit of fiddling around, I was able to get to the annular eclipse. This was off on the other side of Kerguelen Island, so my guess was a little bit off. We are going to make the horizon perfectly flat because this eclipse, the annular portion of this eclipse, happens just as the Sun rises. Now that we’re in the right location, the coordinates ar 48° 32′ south 63° 15′ east. It is a little bit tough to see with the atmosphere, but the Sun is covered about 99.7%, just enough for a little bit of the Sun to be sticking out above and below. Of course, that only lasts for a couple of seconds, so we need to be right on the money, as it were, to get that ring of fire around the edge.

So that was a hybrid eclipse, it was a total eclipse from Timor Leste and parts New Guinea. It was an annular eclipse for down in the southern Indian Ocean, a total eclipse for parts of Australia as well, and then an annular eclipse again back up here in the Pacific. Given that it took so long to hunt around for the exact moment of annularity down south, I’m not going to do it for the other side, it could take quite a while. That is a hybrid eclipse, annular for its beginning and its end, total for its central portion. A very rare type of eclipse, and again, rare at 3%, not the rarest thing that happens.

I very much hope you enjoyed this piece, there will be a piece on the annular eclipse that’s happening in just a few day. I hope you get to see it, you know, if you’re in Antarctica, if you’re a penguin and you’re reading this video then I hope you enjoy the annular eclipse. Or, if you’re in the very south of the south island of New Zealand, you might catch it there as well. I hope that you enjoyed this piece, if you did 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.