Wednesday 25 August 2021

Mercury isn't named Mercury because it's fast

The planets from Mercury to Saturn got their names from Roman gods. How were the names chosen? Here are the explanations given by the International Astronomical Union’s Working Group for Planetary System Nomenclature:

  • Mercury: ‘Named Mercurius by the Romans because it appears to move so swiftly.’
  • Venus: ‘Roman name for the goddess of love. This planet was considered to be the brightest and most beautiful planet or star in the heavens.’
  • Mars: ‘Named by the Romans for their god of war because of its red, bloodlike color.’
  • Jupiter: ‘The largest and most massive of the planets was named Zeus by the Greeks and Jupiter by the Romans; he was the most important deity in both pantheons.’
  • Saturn: no reasoning given (just ‘Roman name for the Greek Cronos, father of Zeus/Jupiter’.)

These explanations are entirely bogus. They’re made up.

The solar system bodies known in antiquity: the earth and the seven moving bodies (planētai, including moon and sun)

You might say it’s not a big deal, no one minds, it doesn‘t make a difference what the historical reasons for the names are. That’s all true. Still, here are some counter-points:

  1. These are literally the people in charge of planets’ names. They had one job!
  2. These explanations get repeated whenever anyone wonders how the planets got their names. If you make up something and it gets repeated as fact all over the world, that’s not OK.
  3. It’s not as though it’d be hard to get it right. You just need to open a book written by someone who knows something about ancient astronomy. If anyone’s going to do make that minimal effort, you’d think it would be the people who are bloody well in charge of planets’ names.

The IAU has professional reasons to take an interest in the history of the names, sure. That doesn’t mean they’re experts. It’s painfully clear that they couldn’t care less what real experts have to say.

For reference, here’s a sample of people who have been misled, often introducing some new fictional material along the way: The Washington Post (7 October 2016), Universe Today (Mercury, Venus, Jupiter, Saturn; Mars omitted), Cornell University,, Science ABC (along with the bizarre claim that Venus was first observed by the Maya), Planets for kids, Wonderopolis,, Quora (Dec. 2020), StackExchange, and the Name Explain YouTube channel (with the bonus howler ‘Roman gods were based on Greek gods’). A number of social Q&A sites since 2013 have referred to an author called ‘Dustin Chiasson’ with similar explanations, but ‘Dustin Chiasson’ appears to be another fabrication.

Let’s consider some more detailed points.

1. Mercury.

It orbits the sun at a velocity of 50 km/s, so the Romans appropriately named it after their swiftest god, Mercury.

No. Ancient astronomers had no way of measuring Mercury’s real orbital speed. They could only observe its apparent motion. And while Mercury bounces from one side of the sun to the other more frequently than Venus, their apparent speed isn’t much different.

Mercury’s real orbital speed is faster, but when they’re on the near side of the sun Venus is closer and that makes up nearly all the difference. In transits of the sun, for example, both planets transit at roughly the same speed, about an eighth of the sun’s diameter per hour. (Not that ancient astronomers observed transits of Mercury or Venus! This is just a convenient direct comparison.) For real information about what ancient astronomers thought about their motions, see Van der Waerden 1982.

If you’re choosing a planet to assign to a messenger god, you’d be better to choose the planet that travels the furthest. Mercury’s apparent position always stays within 28° of the sun; Venus ventures as far as 47° away, and the outer planets go all the way around the sky.

In ancient Babylonian astronomy, by the way, some planets’ names did reflect their apparent motion. The Akkadian name for Mercury, Šihṭu ‘attack, jump’, nicely matches its yo-yo-like motion around the sun; Saturn’s name, Kayyamānu ‘steady’, suits its slow motion. But there’s no indication of anything like that in connection with the gods linked to those planets.

2. Venus. Venus is the brightest planet (not counting the sun and moon, which ancient astronomers did count as planets). But who says brightness is ‘beauty’? Not anyone ancient, I can tell you that. Besides, Venus/Aphrodite’s field of interest wasn’t beauty, if anything it was lust, passionate sexual desire. The ‘brightness = beauty’ explanation isn’t just wrong, it’s also prudish.

At one time, some of the astronomers in the ancient past thought that Venus was actually two stars. This was due to the fact that it appeared as both the morning and the evening star.

Not true. Ancient astonomical texts are perfectly clear that the ‘light-bringer’ and ‘evening star’, or rather Greek Phosphoros and Hesperos, were two names for the same planet (see e.g. Cleomedes, On the heavens 1.2). The same applies to most other ancient civilisations that had multiple names for the inner planets: for example, see Quark 2019 on ancient Egyptian astronomy. In Greek, Homer actually gives us three names for Venus: see below.

3. Mars. In some other ancient cultures Mars does have a name that probably reflects its redness, such as the Chinese name Huǒxīng ‘fire star’, or the late Egyptian form ‘Horus the red one’. That doesn’t impose an obligation on the Romans to do the same, and anyway those names denote ‘red’, not ‘bloody’. I haven’t found any Greco-Roman source that links Mars’ colour to blood.

4. Jupiter.

Jupiter shares a title with the king of the gods because it's the solar system's giant.

Ancient astronomers certainly did not know Jupiter’s size. They had no way of measuring its radius or mass. This is from the science column, by the way: this writer wasn’t just ignoring ancient evidence, they were trying really hard to avoid imagining how the planets look when you don’t have a telescope.

5. Saturn.

Saturn is the last planet visible in the sky without any kind of aid, and named after the Roman god for agriculture–introducing agriculture to the people. The Greek equivalent to Saturn is Kronos — and both govern time (as well as the harvest we just established).

Saturn may have been an agricultural god, but it’s doubtful whether Kronos was. Conversely, in some contexts Kronos could indeed be imagined as having something to do with time (Greek chronos), in mystical forms of Greek religion that drew on name-magic. But that’s Kronos, not Saturn, and the mystical wordplay has no bearing on astronomy anyway.

The actual origins of the names

The names are simply translations. ‘Mercury’, ‘Venus’, etc. are romanised versions of the Greek names ‘star of Hermes’, ‘star of Aphrodite’, and so on. And the Greek links to various divinities were in turn borrowed from links to Babylonian divinities in Babylonian astronomy.

Addendum, an hour later: for maximum clarity, this is as far as we can push the explanation. The evidence trail ends with Nabu, Ishtar, Marduk, etc. We can’t know why Babylonian astronomers linked those gods to those planets: we can only point out that they weren’t gods of ‘speed’, ‘beauty’, and so on. Basically, the real explanation boils down to: ‘Because tradition.’
Old Babylonian cylinder seal depicting Ishtar/Inanna, with Venus shown as an eight-pointed star to the left (Oriental Institute Museum, Chicago; source: Wikimedia, CC BY 3.0)

For accurate accounts of planetary naming systems in antiquity, your top pick for an online source is the Oxford research encyclopedia of planetary science. For Roman and Greek names, see ‘The moon and the planets in classical Greece and Rome’, in the subsection ‘The planets’ (Hannah 2020); and for the Babylonian naming system, ‘The moon and planets in ancient Mesopotamia’, in the subsection ‘The moon, the sun, and the planets in religion, cult, and mythology’ (Ossendrijver 2020). The Encyclopedia covers several other ancient and non-European civilisations too. Neugebauer also has some good material on the Babylonians (1955: ii.498-503, ii.467-497), and the most detailed account of Greek naming systems is an older article by Franz Cumont (1935), who also covers regional variations.

Here are the planet naming systems side by side: English/Latin, Greek, and the Babylonian systems.

Latin, English Associated Greek god(s) Associated Babylonian god(s) Akkadian name
Sol/sun Hyperion, Helios (‘sun’) Šamaš Šanšu
luna/moon Selene Suen/Sin Sīnu
Mercury Hermes, Apollo Nabu, Ninurta Šihṭu (‘rising, attack, jump’)
Venus Aphrodite, Hera Ishtar Dilbat (‘radiant’?)
Mars Ares, Herakles Nergal Ṣalbatānu (meaning unknown)
Jupiter Zeus Marduk, Šulpaea Peṣû (‘white’), Mulbabbar, Sagmegar, Nēberu, etc.
Saturn Kronos Ninurta, night-time version of Šamaš Kayyamānu (‘steady’)

Now, there are a few catches.

  • The Romans put a lot of work into linking their native gods to Greek gods. That’s how we got to having Mercury identified with the Greek god Hermes, Venus with Aphrodite, and so on. That isn’t the same things as Mercury being derived from Hermes. Only a handful of Roman gods were actual imports.
  • With other pantheons things aren’t nearly as tidy. In particular, with the Babylonian gods there’s no real sense of qualities like ‘god of messengers’, ‘god of beauty’, and so on. When Greek astronomers borrowed the Babylonian set of links between gods and planets, Ishtar could be treated as an equivalent to either Aphrodite or Hera depending on context. Some places like Anatolia and Egypt had their own equivalences. (For details about regional variants, see Cumont 1935.)
  • No one thought the planets actually were gods. Greek astronomers called them ‘star of Hermes’, ‘star of Aphrodite’, and so on. Planets could however metaphorically represent the gods in some poetic contexts, like when the Neo-Platonic Hymn to Ares (5th cent. CE?) refers to the god as ‘whirling [his] fiery sphere among the sevenfold courses of the aether’.
  • The borrowed names were in use in the Greek world by the time of Plato (Hannah 2020). The borrowing from Babylonian astronomy probably took place in the 5th century BCE, a few decades earlier. Things are unclear because we don’t have any tracts written by astronomers in that period.
  • Prior to that borrowing, we know almost nothing about homegrown Greek planet names. The only ones we know of are three names for Venus that appear in Homer: Eosphoros ‘dawn-bringer’, Eoios ‘morning (star)’, and Hesperos ‘evening (star)’.
  • In Babylonian astronomy the planets had their own names, as well as being associated with a god. It’s only the divine names that survived translation into Greek and Latin.
  • Egyptian astronomy doesn’t have anything much to do with the Greek naming system. The ancient Egyptians named all of the outer planets after Horus (Mars = ‘Horus of the horizon’, Jupiter = ‘Horus who bounds the two lands’, Saturn = ‘Horus bull of the sky’), and until relatively late their ‘morning star’ was Mercury, not Venus. (See Quack 2019.)

Alternate names: ‘shiny’, ‘shiny’, ‘shiny’, ‘shiny’, and ‘shiny’

Finally, there was an alternate set of Greco-Roman names based on words for ‘shiny’. The alternate names only pop up from Ptolemy onwards, and when they are mentioned they’re normally explained by referring to the divine names. Here’s how Martianus Capella introduces them (viii.851, trans. Stahl and Johnson):

Saturn is called ‘the Shiner’ (Phaenon), and Jupiter ‘the Blazer’ (Phaëthon), and Mars ‘the Fiery’ (Pyrois), Venus ‘the Light-Bringer’ (Phosphoros), and Mercury ‘the Twinkler’ (Stilbon).

In other words, the divine names were the older system, and it seems they were always more standard. Latin translations of the alternate Greek names could also be used.

Latin, English Alternate Greek name Alternate Latin name
Mercury Stilbon Scintillans
Venus Phosphoros Lucifer
Mars Pyroeis Rutilus
Jupiter Phaethon Splendidus
Saturn Phainon Lucidus

These alternate names aren’t very distinctive in meaning. I’d guess that in this system it was harder to remember which planet is which. It isn’t surprising that the older god names continued to stick.


  • Cumont, F. 1935. ‘Les noms des planètes et l’astrolatrie chez les grecs.’ L’antiquité classique 4.1: 5–43. [Persée link]
  • Hannah, R. 2020. ‘The moon and the planets in classical Greece and Rome.’ In: Oxford research encyclopedia of planetary science, online [DOI link]
  • Neugebauer, O. 1955. Astronomical cuneiform texts, 3 vols. Princeton (reprinted New York, 1983).
  • Ossendrijver, M. 2012. Babylonian mathematical astronomy: procedure texts. New York.
  • —— 2020. ‘The moon and planets in ancient Mesopotamia.’ In: Oxford research encyclopedia of planetary science, online [DOI link]
  • Quack, J. F. 2019. ‘The planets in ancient Egypt.’ In: Oxford research encyclopedia of planetary science, online [DOI link]
  • Van der Waerden, B. L. 1982. ‘The motion of Venus, Mercury and the sun in early Greek astronomy.’ Archive for History of Exact Sciences 26.2: 99–113. [JSTOR link]

Saturday 14 August 2021

‘Archaeologists claim they’ve discovered the Trojan Horse’

It’s been reported in a handful of news sources that ‘archaeologists claim to have found a Trojan horse in Turkey’. The story appeared first in Greek Reporter, and it’s been repeated in The Jerusalem Post, Illinois News Today, and IBTimes India in the last four days.

This is just a quick note to repeat what others have already pointed out, especially Spencer McDaniel at Tales of Times Forgotten, plus an update here (just in case anyone is reading this who doesn’t already follow Spencer!):

Every bit of the story is complete fiction.

Addendum, 15 August: It now turns out that the story originated on a satirical website. See Spencer McDaniel’s response below. The real Christine Morris found out the story’s actual origin (archived link provided by Twitter user AlCabbage045). It first appeared there on 29 September 2014. It popped up again on a couple of Greek-language blogs on 5 November that year (here and here), then Greek Reporter picked it up from one of those blogs the following day.
The wooden horse as it appears in A Total War saga: Troy (2020). This week, news sites are competing for historical realism against ... video games.

The real news here is that Greek Reporter is fine with publishing fictional stories, and that The Jerusalem Post, Illinois News Today, and IBTimes India urgently need to upgrade their fact-checking processes.

Even, infamous for passing fiction off as history, didn’t fall for this nonsense. If you’re a news site editor and has better fact-checking than you do, you’ve got a big problem.

(By the way don’t worry, the links in the first paragraph above are to snapshots on The Internet Archive, not to the news sites themselves. They don’t deserve the benefits of Google’s ranking algorithm.)

A few corrective points, as briefly as possible:

The ‘journalist’ repeated the story from an equally fraudulent piece that he made up in 2014. Here’s the original. The 2021 version has alterations in the first four paragraphs. At first Spencer McDaniel thought the two stories were identical, misled because the URL of the 2014 article redirects to the 2021 version of the article. But the November 2014 version is still available through the Internet Archive.

By the way, no one paid any attention to the 2014 story either. Because it was just as fake then as it is now.

Turkish or American? The headline claims that the ‘discovery’ was made by Turkish archaeologists; the article refers to archaeologists at Boston University.

Boston University has never been involved in excavation at Troy. All excavations since 1988 have been under the auspices of the universities of Tübingen, Cincinnati, and Çanakkale.

The archaeologists don’t exist. Here are lists of the faculty at Boston University’s archaeology department and classics department: they’re great people, but there’s no one there called Christine Morris or Chris Wilson. The names are completely made up.

There is a real classical archaeologist named Christine Morris at Trinity College Dublin, in Ireland, as Spencer McDaniel found. But Spencer got in touch with her, and over the last day she’s been kind enough to confirm that

she has never been affiliated with Boston University in any way, that she has never excavated at Troy or worked there in any capacity, that she has never claimed to have found the Trojan horse, and that the story that has been published by Greek Reporter and all these other news outlets is completely fabricated.

The source is fake too. The 2014 article claimed that the story came from, a Greek-language news outlet. This sourcing was removed in the 2021 version of the article. has never published anything on the subject. (The only appearance of the phrase Δούρειος Ίππος on before the 2014 Greek Reporter article is a metaphorical use, in a piece about the racist group Golden Dawn.)

The ancient documentation is fake. Both the 2014 and 2021 versions of the article cite

a damaged bronze plate with the inscription “For their return home, the Greeks dedicate this offering to Athena.” Quintus Smyrnaeus refers to the particular plate in his epic poem “Posthomerica” ...

There was no writing in Greece between around 1150 and 800 BCE: the classical-modern Greek alphabet didn’t develop until the 700s. All Late Bronze Age documents in Greek would have to be written in the Linear B script, and classical-era Greeks weren’t even aware of the existence of that writing system. You’ll be unsurprised to hear that actual mycenologists — scholars who study documents written in the Linear B script — know perfectly well that this story is false. And Quintus of Smyrna, a poet who lived more than a thousand years later than Homer, has nothing at all to contribute to any conversation about these myths.

The lead image from the 2014 version of the Greek Reporter article. Annoyingly, I haven’t been able to track down where they swiped it from: it’s uncredited, and they stripped EXIF and other metadata.

Real archaeologists, real Homer scholars, and real mycenologists have been rolling their eyes at this story. It isn’t a big deal: as I mentioned, the vast majority of news sources have ignored it because it’s so obvious that it’s fake.

But it’s always worthwhile to have another voice pointing out that Greek Reporter and the ‘journalist’ Philip Chrysopoulos apparently feel free to spread misinformation and deceive their readers.

There’s very little reason to see anything historical about the wooden horse itself, or the Trojan War. But that’s a story for another day. I talked about it a bit back in 2016 here, here, and here. I’m planning to revisit the topic a bit more directly soon.