Mentioned previously, Aldebaran was called Borgil by Tolkien. But, it’s not so easy to figure that out just by reading the book.
Here’s what the text looks like.
Away high in the East swung Remmirath, the Netted Stars, and slowly above the mists red Borgil rose, glowing like a jewel of fire. Then, by some shift of airs all the mist was drawn away like a veil and there leaned up, as he climbed over the rim of the world, the Swordsman of the Sky, Menelvagor with his shining belt. The Elves all burst into song.
This was from Chapter 3 of The Fellowship of the Ring. This, as far as I know, is the only reference to Borgil. Now, Remmirath is easy to figure out, it’s probably the Pleiades. That makes sense. And Menelvagor with his shining belt also is clearly Orion, as he also has a shining belt made of Alnitak, Alnilam, and Mintaka, which are interesting stars themselves. Menelvagor is also mentioned quite a bit elsewhere in the legendarium, for example in The Lost Tales and the Silmarillion.
But Borgil is a bit of a mystery. It appears that it rises before Menelvagor, as it was above the mists, and Menelvagor only showed up after the mists had cleared. This may not sound like a mystery, as there is a bright orange star called Aldebaran with which we are now familiar in Taurus that rises between them. However, in that proximity of the sky there is also a much much brighter star, one of the brightest in the sky, and it glows with a distinct red colour. That star is called Betelgeuse, and it’s on Menelvagor’s left shoulder.
Under almost every circumstance if a student were to describe netted stars and then a big ass red one rising later, I’d say it was Betelgeuse. Even if the student says it was different from Orion, I’d assume a mistake. But, in a published work like LOTR, and its cosmology, I don’t think we can assume a mistake here.
There is another option, though, and that is Mars. Mars was actually identified, though, as Karnil. Borgil vs. Karnil. So it’s clear it’s not Mars. Or is it?
Karnil comes from Quenya, one of the Elvish languages, carn for red, and nil from ngil, which is a variation of gil, which we all know to be star. And Borgil, as proven in a letter from Tolkien, comes from Sindarin, another Elvish language, where bor means red, and gil still means star. So now we’re looking at red star in Quenya and red star in Sindarin. These could, in fact, be the exact same star, just with a different language. This is not unprecedented in Tolkien’s cosmology, as Remmirath is known in Westron as The Netted Stars, which is simply a literal translation of the Sindarin. Rem meaning mesh, mir, of course, meaning jewel (often interchangeable with star), and ath, which is a collective plural. So, why couldn’t Karnil be Borgil? No reason, but few suggest it, and I believe I am the only one who has suggested the linguistic connection between them.
It also explains why it’s notable. Mars, of course, wanders about in the sky, as it’s a planet, and spends time in many constellations, one of which is Taurus, the container of much of the celestial area we are discussing. We don’t know how far away in time LOTR occurred. The years aren’t clear. All we know is that it’s in the past, so we can’t confirm the position of Karnil for this, but we can confirm the plausibility, as shown.
Here we have Menelvagor rising, with the Remmirath high in the sky, arbitrarily defined by me at above 45 degrees. We also have our three Borgils, Mars, Aldebaran, and Betelgeuse. Mars can be stupid bright, multiple times brighter than Betelgeuse or Aldebaran, so this could be our Borgil…but this doesn’t happen very often, and maybe Tolkien would have mentioned its status as a wanderer.
So let’s look back at Betelgeuse. I said I’d almost always suggest this as a candidate, but I don’t think it works here. Let’s look at the text. Borgil is above the mist, Menelvagor is below. Betelgeuse can’t work like that. The head stars of Menelvagor and his shoulder star, known today as Bellatrix, rise well before Betelgeuse, as seen.
Bellatrix is indicated here during Orion’s rising. Hence, I think Tolkien wouldn’t say that Menelvagor is revealed when quite a few parts of him were up BEFORE Borgil, with no mention of any stars in between Remmirath and Betelgeuse. I don’t buy it.
Now Aldebaran is plausible as a red star that would be above the mist and still hold Menelvagor below it. Like this.
Now we have the whole of Menelvagor: Saiph, Rigel, Betelgeuse, Bellatrix, and so on. So maybe it was Aldebaran. It’s a bright orangey star, but it’s not as bright as Betelgeuse or Mars, though it fits the other characteristics, and is always there, which is why I call it Borgil, but it’s up for debate.
So, I think we can conclusively say that Betelgeuse isn’t Borgil, despite what dozens of websites say, some linked at the bottom, and we can definitely say that Aldebaran could be, and so could Mars.
Pros and cons of Aldebaran:
Pros: 1. Orange. 2. Right place.
Cons: 1. Not AS notable as others in the area.
Pros and cons of Mars:
Pros: 1. Red. 2. Right place. 3. Ultra notable. 4. Language link.
Cons: 1. Transient. 2. Possibly exclusively named Karnil.
So, is Borgil Mars or Aldebaran? I like to say it’s Aldebaran to students who are trying to learn the sky, since Mars is noticeable enough. But, as we can see by my totally scientific pros and cons list, they’re about dead even in the plausibility. If there is a Tolkien scholar better than me out there who is more familiar with his writings on the subjects, I’d quite enjoy knowing if Mars can be conclusively proven to not be Borgil.
TL;DR. Aldebaran. Maybe Mars. But Aldebaran.
Again, if you look for more info on this online, you likely won’t find much about the plausibility of Mars. I think I am the only one who came up with the idea Mars could work here.
Tolkien related bibliography (some of these have bad information, which made me write this article up):
http://www.glyphweb.com/arda/m/menelvagor.html
http://www.glyphweb.com/arda/b/borgil.html
http://tolkiengateway.net/wiki/Menelvagor
http://tolkiengateway.net/wiki/Borgil
http://thainsbook.net/stars.html
http://www.physics.ccsu.edu/larsen/borgil1.pdf
http://www.physics.ccsu.edu/larsen/borgil2.pdf
http://tolkiengateway.net/wiki/Three_is_Company
http://lotr.wikia.com/wiki/Borgil
http://tolkiengateway.net/wiki/Remmirath