# Why is Jupiter called Jupiter? **URL:** \ **Category:** Factual Questions\ **Created:** [May 29, 2015, 3:58pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127 "2015-05-29T15:58:22Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![The\_Hamster\_King](https://avatars.discourse-cdn.com/v4/letter/t/8edcca/32.png) [@The\_Hamster\_King](https://boards.straightdope.com/u/The_Hamster_King)\ **Post date:** [May 29, 2015, 6:58pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/21 "2015-05-29T18:58:32Z")
The planets weren’t named for the gods. The planets WERE the gods. You look up in the night sky and you notice that some of the lights are wandering around. Clearly they must be beings who live up in the sky! It would be like seeing campfires off in the distance and deducing there must be another tribe living over there. How the different lights look and behave tells you what kind of people they are. Saturn is faint and hobbles along slowly like an old man. Jupiter is bright and moves sedately across the entire sky with the dignity befitting a king. Mars is red like blood – he must be a warrior. Venus is beautiful but shy – she only comes out in the morning and evening. And Mercury is fast – he must be running back and forth carrying messages. ---
**Author:** ![Saint\_Cad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saint_cad/32/18907_2.png) [@Saint\_Cad](https://boards.straightdope.com/u/Saint_Cad)\ **Post date:** [May 29, 2015, 7:19pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/22 "2015-05-29T19:19:00Z")
> [@Really\_Not\_All\_That\_Bright](#): > > What reason did the ancients have to assume that planets moved at the same speed, though? They don’t; Jupiter is orbiting at about four tenths Earth’s speed (and in fact all the planets appear to move at speeds that are correlated to the size of their orbits, with the nearest planets moving faster.) OK so assuming Kepler did not write up his work in 2000BC, why would you assume the planets DIDN’T move at the same speed in their orbit. ---
**Author:** ![Ornery\_Bob](https://avatars.discourse-cdn.com/v4/letter/o/da6949/32.png) [@Ornery\_Bob](https://boards.straightdope.com/u/Ornery_Bob)\ **Post date:** [May 29, 2015, 7:21pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/23 "2015-05-29T19:21:52Z")
If I remember correctly, there are times when the apparent size of Jupiter exceeds that of Venus, so regardless of actual size, Jupiter is often the “largest” planet in the sky after the moon and the sun. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [May 29, 2015, 7:23pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/24 "2015-05-29T19:23:20Z")
> [@Saint\_Cad](#): > > OK so assuming Kepler did not write up his work in 2000BC, why would you assume the planets DIDN’T move at the same speed in their orbit. Because there’s no reason to think they would. Other things don’t move at the same speeds; why would planets? ---
**Author:** ![bup](https://avatars.discourse-cdn.com/v4/letter/b/6bbea6/32.png) [@bup](https://boards.straightdope.com/u/bup)\ **Post date:** [May 29, 2015, 7:24pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/25 "2015-05-29T19:24:05Z")
> [@The\_Hamster\_King](#): > > The planets weren’t named for the gods. The planets WERE the gods. Nope. [The Hymn to Ares](http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.01.0138%3Ahymn%3D8) makes it pretty clear it’s a heavenly body associated with, or under the control of, Ares, but wasn’t the god hisself. And _**[Plato’s Timaeus](http://www.gutenberg.org/files/1572/1572-h/1572-h.htm)**_ says that the planets are not gods, and that the planets, sun and moon do not move at uniform speed, but in proportion. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [May 29, 2015, 7:33pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/26 "2015-05-29T19:33:10Z")
> [@Ornery\_Bob](#): > > If I remember correctly, there are times when the apparent size of Jupiter exceeds that of Venus, so regardless of actual size, Jupiter is often the “largest” planet in the sky after the moon and the sun. That would not have been evident to the naked eye, however. ---
**Author:** ![The\_Hamster\_King](https://avatars.discourse-cdn.com/v4/letter/t/8edcca/32.png) [@The\_Hamster\_King](https://boards.straightdope.com/u/The_Hamster_King)\ **Post date:** [May 29, 2015, 7:46pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/27 "2015-05-29T19:46:09Z")
> [@bup](#): > > Nope. > > [The Hymn to Ares](http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.01.0138%3Ahymn%3D8) makes it pretty clear it’s a heavenly body associated with, or under the control of, Ares, but wasn’t the god hisself. > > And _**[Plato’s Timaeus](http://www.gutenberg.org/files/1572/1572-h/1572-h.htm)**_ says that the planets are not gods, and that the planets, sun and moon do not move at uniform speed, but in proportion. The classical Greeks are far too modern to be reliable sources for the origins of names of the planets. We need to look at reconstructions of stone age beliefs. [When They Severed Earth From Sky](http://www.amazon.com/When-They-Severed-Earth-Sky/dp/0691127743) gives a good accounting of this theory. ---
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [May 29, 2015, 8:12pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/28 "2015-05-29T20:12:23Z")
> [@Colibri](#): > > The first Greek cosmology was by [Anaximander](http://www.iep.utm.edu/anaximan/#SH6f) (610-646 BC). He put the stars closest to the Earth, then the Moon, then the Sun, which is rather the opposite of the assumption that the brightest objects must be closest. I haven’t found a reference to Anaximander’s concept of the planets if any… Wow, DATA!! And research!! What a concept. ---
**Author:** ![Kimstu](https://avatars.discourse-cdn.com/v4/letter/k/ecd19e/32.png) [@Kimstu](https://boards.straightdope.com/u/Kimstu)\ **Post date:** [May 29, 2015, 8:17pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/29 "2015-05-29T20:17:39Z")
Classical planetary names were initially adopted from Babylonian ones (along with numerous other features of Babylonian astronomy), so there’s no point arguing about how or why the ancient Greeks chose to assign certain deities to certain planets. **The ancient Greeks were not the ones who came up with that idea.** The deities assigned to the planets in Babylonian astronomy were Ninib, Marduk, Nergal, Ishtar, and Nabu for Saturn, Jupiter, Mars, Venus and Mercury respectively. Greek astronomers adapted those identifications to correspond to the deities that seemed most similar in the Greek pantheon. E.g., Ishtar was a female deity of fertility and love (among other things), hence Aphrodite/Venus; Nergal was a fiery deity of destruction and war, hence Ares/Mars. ---
**Author:** ![Kimstu](https://avatars.discourse-cdn.com/v4/letter/k/ecd19e/32.png) [@Kimstu](https://boards.straightdope.com/u/Kimstu)\ **Post date:** [May 29, 2015, 8:38pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/30 "2015-05-29T20:38:55Z")
How and why the ancient Mesopotamians originally came up with the particular deity/planet associations that still persist today is by no means clear, partly since the system probably originated at least 4000 years ago. But there are some informative speculations in Jastrow’s [_Aspects of Religious Belief and Practice in Babylonia and Assyria_](https://books.google.com/books?id=mZQKqgjm_AwC&pg=PA226&lpg=PA226&dq=Jastrow+Marduk+Jupiter&source=bl&ots=fZ8ppsfoil&sig=mWUumGDtQk1gGC4NjuKPr1Tfsiw&hl=en&sa=X&ei=_MloVafgLvDksATfzIGAAg&ved=0CDQQ6AEwBA#v=onepage&q=Jastrow%20Marduk%20Jupiter&f=false). A more up-to-date discussion is Francesca Rochberg’s “What is the nature of the heavenly bodies?” in D. Snell’s [_Companion to the Ancient Near East_](https://books.google.com/books?id=REVFoXJM4WIC&pg=PA327&lpg=PA327&dq=Pingree+Hunger+planet+names+Marduk+Nabu&source=bl&ots=zuK_QkmusY&sig=kjbI_pjDQ66tPlLnD30Rbwyn0V8&hl=en&sa=X&ei=LsxoVa7HFdHasASihoLACw&ved=0CB8Q6AEwAA#v=onepage&q=Pingree%20Hunger%20planet%20names%20Marduk%20Nabu&f=false): > [@](#): > > Sumerian hymns reveal that already in the third millennium the planet Venus was seen as the astral form of the goddess Inana or Istar […] > > Jupiter was identified with the god Marduk […] The manifestations of that god in the various appearances of Jupiter took on other names […] when in the middle of the sky, “the Ford.” In all these guises, Marduk/Jupiter was “the bearer of signs to the inhabited world” […] > > One of the names of Mercury was “the jumping one,” which could have been descriptive of the planet’s fast motion and perhaps the fact that it was not often or easily visible. Mercury was associated with the gods Ninurta and Nabu symbolizing the crown prince or son of Marduk […] The association of Mercury with the two gods may relate to the appearances of the planet as a morning and evening star […] > > Mars was associated with Nergal, god of pestilence […] > > The luminous aspect of the heavenly divine manifestations was their most obvious quality. In Sumerian liturgy the radiance of Venus was frequently mentioned. […] In the creation poem Marduk’s ninth name was “bright one,” “the shining god who illumines our ways,” and his forty-ninth name was “Ford” = Jupiter, “the star which in the skies is brilliant” […] ---
**Author:** ![Petrobey\_Mavromihalis](https://avatars.discourse-cdn.com/v4/letter/p/bcef8e/32.png) [@Petrobey\_Mavromihalis](https://boards.straightdope.com/u/Petrobey_Mavromihalis)\ **Post date:** [May 29, 2015, 8:40pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/31 "2015-05-29T20:40:46Z")
> [@Smeghead](#): > > Wow, DATA!! And research!! What a concept. I’m not understanding the nature of your contribution to the discussion. ---
**Author:** ![Saint\_Cad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saint_cad/32/18907_2.png) [@Saint\_Cad](https://boards.straightdope.com/u/Saint_Cad)\ **Post date:** [May 29, 2015, 8:52pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/32 "2015-05-29T20:52:32Z")
> [@Really\_Not\_All\_That\_Bright](#): > > Because there’s no reason to think they would. Other things don’t move at the same speeds; why would planets? Well pick one or the other and base it on science & philosophy know at the time. ---
**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\ **Post date:** [May 29, 2015, 9:33pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/33 "2015-05-29T21:33:38Z")
> [@Petrobey\_Mavromihalis](#): > > I’m not understanding the nature of your contribution to the discussion. I am pointing out that, as a group, we are awfully quick to throw out speculative answers that seem reasonable on the surface, when perhaps it would be wiser to look for actual supportable answers based on actual solid information first. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [May 29, 2015, 10:42pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/34 "2015-05-29T22:42:11Z")
> [@Saint\_Cad](#): > > Well pick one or the other and base it on science & philosophy know at the time. Huh? ---
**Author:** ![Saint\_Cad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saint_cad/32/18907_2.png) [@Saint\_Cad](https://boards.straightdope.com/u/Saint_Cad)\ **Post date:** [May 30, 2015, 12:33am UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/35 "2015-05-30T00:33:42Z")
> [@Really\_Not\_All\_That\_Bright](#): > > Huh? You contend that it is a natural assumption that the planets travel at different speeds. If you did not know about Kepler’s Laws or the inverse-square law of gravity then why is that a natural assumption? The assumption that all planets travel at the same speed is a much more natural one because you don’t have to answer the question of WHY they travel at different speeds. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [May 30, 2015, 12:34am UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/36 "2015-05-30T00:34:24Z")
> [@Smeghead](#): > > I am pointing out that, as a group, we are awfully quick to throw out speculative answers that seem reasonable on the surface, when perhaps it would be wiser to look for actual supportable answers based on actual solid information first. You must be new around here.😉 ---
**Author:** ![Kimstu](https://avatars.discourse-cdn.com/v4/letter/k/ecd19e/32.png) [@Kimstu](https://boards.straightdope.com/u/Kimstu)\ **Post date:** [May 30, 2015, 1:21am UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/37 "2015-05-30T01:21:52Z")
> [@Saint\_Cad](#): > > You contend that it is a natural assumption that the planets travel at different speeds. If you did not know about Kepler’s Laws or the inverse-square law of gravity then why is that a natural assumption? Wait, _what_? The planets _as perceived in the sky with the naked eye_ most certainly **do** “travel” at different speeds among the fixed stars. That’s no “assumption”, that’s a plain and simple **observation**. Look at Venus, for example, from one night to the next over a few days and you’ll notice that it quite detectably changes its position with respect to the fixed stars around it. It takes much longer to see the same kind of position shift for Jupiter or Saturn, say. That’s what the ancients meant when they spoke of some planets being “fast” and others “slow”. Now, if you’re trying to put that observed position shift into some kind of **kinematic physical cosmology** , where you develop a model of orbital motion to geometrically describe and predict the position changes you see in the planets, that’s another matter. In that case, you do have to figure out some kind of hypothesis about how fast the planet’s revolving and how far away it is, and tweak the model so that it actually corresponds to what you see in the sky. But there’s certainly nothing “natural” about assuming that that intrinsic angular speed would be the same for all planets. Some ancient geocentric models assumed it was and others did not. ---
**Author:** ![Kimstu](https://avatars.discourse-cdn.com/v4/letter/k/ecd19e/32.png) [@Kimstu](https://boards.straightdope.com/u/Kimstu)\ **Post date:** [May 30, 2015, 1:31am UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/38 "2015-05-30T01:31:05Z")
I think we’re far too liable to project back onto the pre-Greek astronomers our own concepts of 3-D orbital models where the planets revolve in space at different distances from a common center (or focus if we’re being post-Kepler about it). There’s no evidence that the ancient Mesopotamians had any **geometric** models of planetary motion at all. The sky for them was just this surface (not even necessarily a spherical surface) upon which a bunch of bright lights moved in various regular or irregular “paths” that were evidently cyclical and periodic in nature, and thus could be modeled numerically if you accumulated enough data to figure out the patterns. ---
**Author:** ![Saint\_Cad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saint_cad/32/18907_2.png) [@Saint\_Cad](https://boards.straightdope.com/u/Saint_Cad)\ **Post date:** [May 30, 2015, 5:10pm UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/39 "2015-05-30T17:10:01Z")
> [@Kimstu](#): > > Wait, _what_? The planets _as perceived in the sky with the naked eye_ most certainly **do** “travel” at different speeds among the fixed stars. That’s no “assumption”, that’s a plain and simple **observation**. > > Look at Venus, for example, from one night to the next over a few days and you’ll notice that it quite detectably changes its position with respect to the fixed stars around it. It takes much longer to see the same kind of position shift for Jupiter or Saturn, say. > > That’s what the ancients meant when they spoke of some planets being “fast” and others “slow”. > > Now, if you’re trying to put that observed position shift into some kind of **kinematic physical cosmology** , where you develop a model of orbital motion to geometrically describe and predict the position changes you see in the planets, that’s another matter. In that case, you do have to figure out some kind of hypothesis about how fast the planet’s revolving and how far away it is, and tweak the model so that it actually corresponds to what you see in the sky. > > But there’s certainly nothing “natural” about assuming that that intrinsic angular speed would be the same for all planets. Some ancient geocentric models assumed it was and others did not. First of all, I never said same angular velocity. The assumption is the same linear velocity. And as I stated above, the ancients would be familiar with the idea that two objects with the same linear velocity would have different _apparent_ velocities at different distances. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [May 31, 2015, 2:22am UTC](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127/40 "2015-05-31T02:22:03Z")
> [@Saint\_Cad](#): > > You contend that it is a natural assumption that the planets travel at different speeds. If you did not know about Kepler’s Laws or the inverse-square law of gravity then why is that a natural assumption? Because it’s the default assumption, and the one consistent with any observations they might have made. > [@](#): > > The assumption that all planets travel at the same speed is a much more natural one because you don’t have to answer the question of WHY they travel at different speeds. No, you have to answer the question of why they travel at the same speed. Nothing else they might have observed in nature would do that. Waves on the beach, horses, thrown objects, and so on all travel at different speeds. [Previous page](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127.md?page=1) [Next page](https://boards.straightdope.com/t/why-is-jupiter-called-jupiter/721127.md?page=3)