Syzygy and Selenelion

I learned a new word when I was reading the news this morning. Selenelion. Apparently, on Tuesday morning we may be able to see the fully-eclipsed moon and the sun at the same time, which is called a selenelion. The eclipsed moon is also called a blood moon, because when it ducks behind the shadow of the earth, it takes on a reddish color.Actually I also learned a second new word, which is one I’d heard before but wouldn’t have been able to explain what it meant. Syzygy, which is spelled s-y-z-y-g-y, which feels like an extremely unlikely spelling to me, but the meaning is just when the sun, moon, and earth are in a straight line with each other.I got curious about how long we’ve been able to predict astronomical events like these ones and wound up learning about Edmund Halley correctly predicting a solar eclipse in 1715 and then again, even more accurately, in 1724 using lunar tables. But way before that happened, there’s a story that Thales of Miletus predicted a total solar eclipse in 585 BCE, an event that has been called the birth of science. If you want to celebrate it as the birth of science, the exact date you’d celebrate would be May 28th, and this year would be the two-thousand-six-hundred-eleventh birthday, but I’m a little skeptical of the story. It feels to me more like “hey I knew that was going to happen.” I understand that the ancients had a very different model of solar eclipses than Edmund Halley did, although we’re often underestimating them.One thing we do know is that eclipses were often recorded, and that it’s possible now to pinpoint the exact date, like that May 28th date in 585 BCE, which can tell us the exact day and time that the omen occurred, which by the same account that puts Thales of Miletus there, tells us there was a battle going on, and that the eclipse was treated as an omen.Recall that solar eclipses and lunar eclipses are both at syzygys, do you like how I used that word that I just learned the meaning of? In a solar eclipse, the order of the syzygy is sun then moon then earth, so the moon is between the earth and the sun, and the moon casts a smallish shadow on the earth, so it only blocks out the sun in a specific place, which as the relative positions of all three of them change, looks like a shadow traveling in a line across the surface of the earth.In a lunar eclipse like we’re having on Tuesday, the earth is in the middle, and it casts a large-ish shadow on the moon, and everyone on earth who can see the moon sees the same thing. It’s another kind of omen. In the Revelation of John of Patmos in the New Testament, it’s part of the weird prophecy/dream sequence:When he opened the sixth seal, I looked, and behold, there was a great earthquake, and the sun became black as sackcloth, the full moon became like bloodNow, in this prophecy the next thing that happens is the stars fall out of the sky and the figs fall off the fig tree, and then someone rolls up the sky like a scroll. So, grain of salt.But it does seem to be a reasonable enough description of a solar and lunar eclipse that we can pretty easily imagine John of Patmos would have at least had some cultural knowledge of what was going on. And that rings true in ancient sources. In the Old Testament prophet Joel, we hear an echo of the same thing:And I will show wonders in the heavens and on the earth, blood and fire and columns of smoke. The sun shall be turned to darkness, and the moon to blood, before the great and awesome day of the Lord comes.Even though we know the cause of an eclipse is a syzygy, that’s the fourth time today I’ve used the word syzygy, even though we know it, it still seems pretty remarkable. And we still learn something from it. I’m planning to get up on Tuesday and see what I can see, although it might be a little hard to see from Right Field Farm, but the rest of you should get somewhere above the treeline or skyline and make sure you have an unobstructed view to the west, or to the east and the west if you want to see the full selenelion, the sun and the lunar eclipse at the same time.Apparently the atmosphere acts as a prism, which is why even though it’s a syzygy, that’s five, you can still see both the sun and the moon, and the earth for that matter.Before we light our candles and think about all this, I want to read one more eclipse quote from the Old Testament, this one from the prophet Amos, we’re actually going to read two parts of his prophecy. First,He who made the Pleiades and Orion, who turns midnight into dawn and darkens day into night,who calls for the waters of the sea and pours them out over the face of the land— the Lord is his name.Such poetry. It’s not the only time Amos mentions an eclipse, and we know that a total solar eclipse happened where he lived in 763 BCE. We know because we can calculated it, but also because we have contemporary Assyrian sources that mention it.The meaning, again, was different from what we might ascribe to it today, and we’re going to read a little bit more from the prophet Amos.For I know how many are your offenses and how great your sins.There are those who oppress the innocent and take bribes and deprive the poor of justice in the courts.Therefore the prudent keep quiet in such times, for the times are evil.Seek good, not evil, that you may live.Then the Lord God Almighty will be with you, just as you say he is.Hate evil, love good; maintain justice in the courts.Perhaps the Lord God Almighty will have mercyI was especially noticing the verse there in the middle, “therefore the prudent keep quiet in such times,” but I’m going to have to think on it some more. The closing is really what sticks with me from it - “Hate evil, love good; maintain justice in the courts. Perhaps the Lord God Almighty will have mercy.”Let’s light our candles and think about syzygy, there’s my sixth lifelong use of that word, and selenelion together, but let’s also not forget that the turning of the seasons and the spiraling of our little planetary system can still inspire us to turn away from wrong and turn toward good.I love you all so very much, and I can’t believe we get to have all four of you home next weekend, it’s going to be an epic total eclipse of my heart. This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit notesformeeting.substack.com