Ancient astrologers discover Uranus

Hi! I've posted this in the Shared World section as well (isn't that the area reserved for timelines written by committee?)
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I've got an idea for a POD for a timeline I was wondering you could help create with me. It all hinges on something interesting I saw on Wikipedia:

"From 1995 to 2006, Uranus's apparent magnitude fluctuated between +5.6 and +5.9, placing it just within the limit of naked eye visibility at +6.5..."

THE SCENARIO:

An ancient astrologer in Egypt or Mesopotamia ca. 2000-1500 BC is teaching his young apprentice the tools of the trade. He orders his apprentice to study the skies and understand the motions of seven known planets. The apprentice can see how Mercury, Venus, the Sun, the Moon, and Mars move because they move relatively quickly. However, he's dubious that Jupiter and Saturn move. So the master instructs him to take a look at all of the stars around Jupiter and Saturn and jot down, with meticulous precision, how Jupiter and Saturn are moving in relation to the fixed stars. He tells the apprentice to do so for three months, enough time for the two planets to move appreciably.

Unknown to the astrologer's aged eyes (indeed, to anyone), Saturn or Jupiter is having a close conjunction with Uranus. We'll say Saturn for now.

Three months later, the master summons the apprentice and asks for his report. Now keep in mind that younger people often have better eyesight than older ones.

The apprentice explain that he definitely saw Jupiter move. However, he noticed that two objects seemed to move in the area around Saturn. The bright object seemed to move about 3 times as much as the faint object. Which one of them is Saturn? It sure looks to him that there are two planets out there.

The master starts laughing at him but then notices the apprentice's work. It sure sounds like there's something out there. So he helps the apprentice continue on with his experiments. Sure enough, there's a second planet out there near Saturn, one which is almost impossible to see! What's more, that planet seems to be a star! It sure LOOKS like an ordinary star. And if that's a planet, are any of the other "fixed" stars moving as well?

The master naturally decides that this planet can be used to improve the accuracy of his astrological predictions, so he starts using it in his charts. Its existence starts out as a trade secret.

Can you think of the ramifications of this? Here are a few:

1. Astrologers will need to develop better maps of the heavens in order to pinpoint this new planet. After all, there are lots of stars whose magnitude is comparable to Uranus. Astrologers will need to pinpoint all the fixed stars find which one of them is the planet. I am assuming improved optics are out at this time period, so no Neptune, rings of Saturn, or moons of Jupiter.

2. Eight day weeks develop. This divides evenly into the 360 days of the Babylonian year. This can easily be seen as a sign of the god's perfection: obviously, each season is associated with a god and/or planet. Lots of 8's will start showing up in history where we have 7's.

3. Lots more astrologers start looking for planets. After all, it sure looks like a fixed star can be a planet. So they look for others to improve their chances. (If they're lucky, they find asteroid 4 Vesta but that's a long shot). After all, any planet you find will make your predictions more reliable! And kings are more likely to want to hire you!

4. A long shot, but bear with me: As the maps of the heavens get better and better due to people trying to track down Uranus among the faint stars, they get accurate enough to determine the distance in degrees between two points on the celestial sphere. It is not out of the realm of possibility (though it is unlikely) that this could yield primitive longitude values (at least for Mediterranean travels) once people determine Earth is a sphere via the lunar distance method or something like that.

5. The existence of Uranus could alternatively become a serious trade secret which only the elite astrologers (and/or maybe kings) know about. If you don't meet certain qualifications and/or join the right guilds, you don't learn about it and your predictions stay faulty. And if the predictions fail, well it's their fault because they didn't use Uranus. And even the gods won't be able to help you if you let the BAD GUYS across the border find out about this planet (especially where it is...)

6. It may be possible for novae and supernovae to be detected ("what, this star DISAPPEARED?") as maps are compared. Someone says, "Hey, look, a planet appeared out of nowhere" and becomes the laughing stock of the community when the "planet" suddenly fades away.

What do you think? You may assume that with the limited light pollution in the ancient times and the dark skies in deserts (in Egypt and so forth) that under rare circumstances limiting magnitude can hit 7.0 at the zenith. Objects this faint can be seen when they are relatively high in the sky, albeit on rare occasions, atmospheric conditions permitting.

ACG
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P.S. Here's some info on Vesta. It is indeed possible to see Vesta with the naked eye on rare occasions. However, it's very difficult. You may assume that Uranus is found before Vesta. It will be easier to detect movement with Vesta than it will be with Uranus (Vesta will orbit about 3 times faster than Jupiter)

"Asteroid 4 VESTA (magnitude 6.5) is at opposition on October 29th. See above...Have you ever seen an asteroid? If not, your best chance this year [I don't know which year the post is from] is coming up in October. Vesta, the fourth asteroid to be discovered, is at opposition this month, on the 29th. When a body is at opposition, Sun, Earth and the body are in a straight line, with Earth in the middle. At this time the object is up all night and about as close to Earth as it can get."
 

Thande

Donor
Very interesting idea.

However, I suspect astrologers would simply reclassify the moon as not belonging to the planets in order to keep the magic seven number. I seem to remember something along those lines being suggested when Uranus was discovered in OTL.

Also, an alternative might be an early discovery of Vesta, which is visible to the naked eye (barely).
 
I ruled out Vesta as less likely -- it probably ranges from magnitude 6.5 to 7.5 or something like that. Most of the time it would not be visible. Any discovery of Vesta would be extremely difficult to confirm (and even if it did, the asteroid would disappear from view at some point). It could be passed off as a comet.

However, I agree that Vesta is not impossible (particularly if people are looking for planets like they would do after Uranus was discovered). Note also that 8 and 9 could be considered magical numbers by the Babylonians (both are factors of 360).

Perhaps even more intriguing is the possibility of TWO Sabbath days in a 9-day week because resting one day in nine is probably not enough for good health. If Vesta is found and the week gets long enough to warrant another Sabbath day...

Neptune is out of the question, by the way. I think that's 7.9 or something like that.
 
FYI, you might find this interesting:

"Saturn-Uranus: Very close conjunctions <85": 2 Feb 2367 BC and 20 Aug 646 BC"

What was going on in 2367 BC? Could Egypt have been advanced enough to discover Uranus? I can't remember how advanced the early civilizations were at this era.

The 646 BC conjunction would have been easier to detect but there would be fewer butterflies due to the later discovery (including a possible biblical seven-day week).

Jupiter and Uranus did not seem to have any obvious conjunctions during our time period. I would argue that other planets' conjunctions are not going to do much good because the apprentice wouldn't get to see Uranus move in the time it takes for the other planet to wander away. This menas that we've got two dates for Uranus to be discovered (plus or minus a few months)

ACG
 
A while back there was a thread on "types of technology that often get ignored" or something like that. This one - astronomy - definitely fits that category. Very cool.

I'm not sure that this would start an immediate rush to find new planets - I doubt that the ancients were quite as fad driven as we are - but your idea of more careful scrutiny of the heavens seems to make sense to me anyway. It would get astronomers to question their assumptions.

Mainstream archaeology dates the Giza pyramids to c. 2550 BC, and those are oriented precisely enough to be evidence of advanced astronomy in Egypt at that time. So I'd think that a PoD 2367 BC is possible, at least. But I'm no expert.
 
The more I think about it, the more I'm convinced that we're going to eventually wind up with quick determination of longitude (albeit with a decent margin of error) once people figure out the Earth is round. Improved star maps and astromonical observations made by the astrologers really help with the lunar distance method.

I think the Greeks figured out the Earth was a sphere ca. 250 BC or so. With increased observations of the heavens triggered by the discovery of Uranus, you could probably push that back even further. I actually wonder whether Greek mathematicians (indeed, any seafaring power) can figure out Kepler's laws while they're banging on their accurate star charts. In theory, the Earth can still be the center of the universe and the stars fixed, but various combinations of ellipses could help track down the planets with near certainty. And once you get that the lunar distance method becomes pretty easy.

I see major butterflies:

1. CULTURAL: Lots of 8's and 9's (which conveniently divide 360 and could warrant multiple Sabbath days due to the longer week in ancient Judaism) where we have 7's. Association of months and seasons with gods.
2. SCIENTIFIC: Better star maps, including a possible search for a 10th "planet" because 10 seems like a perfect number (number of fingers etc.) and it sounds like something the gods would do. We can assume that they do not know Earth is a planet. They may determine the Earth is round.
3. POLITICAL: Someone combines the star charts and a round Earth to determine longitude via lunar distance. They may underestimate or overestimate the size of the Earth by a decent amount, but they'll know it's round. I really wonder if we'll wind up with Romans or Phoenicians learning about the New World (though probably being unable to colonize it). Now if the Romans and Phoenicians stay long enough to get the Indians accustomed to old world diseases by the time the Europeans get there...

Now of course longitude determination HAS to be a national secret (look what happened with Harrison and his longitude clock). You can't hide the moon and you can't prevent enemy regimes from having bright scientists, but you can hide the accurate star charts. That's the only way you can keep longitude to yourself. A king can probably tell his subjects that everyone will benefit from advanced star maps: the astrologers get better results and the soldiers can explore the world and claim more lands for the Crown.
 
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