Astro WI: Galileo discovers Neptune

Galileo's observation records indicate that in late 1612 he observed the planet Neptune. However, at this time Neptune was just beginning its retrograde cycle and so appeared stationary and too small to be a planet. Galileo took it to be a fixed star.

But what if Galileo had made his observations a few days earlier before the retrograde cycle had begun? He realises that he is observing a previously unknown planet and once he makes a few more observations and confirms this thought, he publishes his findings.

What will the implications of the 'discovery' be?
 
Galileo's observation records indicate that in late 1612 he observed the planet Neptune. However, at this time Neptune was just beginning its retrograde cycle and so appeared stationary and too small to be a planet. Galileo took it to be a fixed star.

But what if Galileo had made his observations a few days earlier before the retrograde cycle had begun? He realises that he is observing a previously unknown planet and once he makes a few more observations and confirms this thought, he publishes his findings.

What will the implications of the 'discovery' be?
Before Uranus!? That would be interesting.

Uranus was discovered as a planet in 1781, Ceres in 1801.

So this would be the first non-classical 'planet' discovered, by a long shot.

OTOH, even if he saw it move, would he not consider it some sort of wierd comet, rather than a planet?

IF it's recognized as a planet, it would be as earth-shattering as sun-spots, and craters on the moon, both of which had major theological and philosophical implications.

If it is thought to be a wierd comet, and is lost, as it might well be, then minimal change.

IMO
 
Before Uranus!? That would be interesting.

Uranus was discovered as a planet in 1781, Ceres in 1801.

So this would be the first non-classical 'planet' discovered, by a long shot.

OTOH, even if he saw it move, would he not consider it some sort of wierd comet, rather than a planet?

IF it's recognized as a planet, it would be as earth-shattering as sun-spots, and craters on the moon, both of which had major theological and philosophical implications.

If it is thought to be a wierd comet, and is lost, as it might well be, then minimal change.

IMO

Actually, Uranus was observed in 1690, but classified as a star named 34 Tauri.

If Galileo discovered Neptune, and proved it was a planet (some other observations at the same time could help him out with that), the idea of celestial perfection is shattered. It relied on the idea of 7 planets in the sky, because 7 is the perfect number (7 days in a week, for example). The classical planets were Mercury, Venus, Moon, Mars, Jupiter, Saturn, and Sol. Neptune breaks that pattern, with a bit more force than the discovery of Jupiter's moons did.

BTW, last year, a physicist from the University of Melbourne asserted that Galileo knew of Neptune's motion.
 
It might have delayed the discovery of asteroids. Bode's Law (a pattern in the distances of planets from the sun which happened to fit everything discovered at the time) doesn't fit Neptune, so it probably wouldn't have been thought up, and asteroids were discovered based on Bode's Law.

I think with more time studying Neptune's orbit, there wouldn't have been a need to go looking for a "Planet X" to explain the "anomalies" which turned out not to exist. That might have meant that Pluto would not have been considered a planet when it was first discovered as OTL, or at least would have been downgraded faster a la Ceres, and people might have been more willing to look for other Kuiper Belt Objects in the meantime.

Another thing to consider is that Neptune was the first planet which was predicted by Newtonian Mechanics first, rather than simply discovered and then shown to fit. Without that, will the mathematical theories be viewed as precise as they were when the prediction proved correct? Probably wouldn't have affected them that much, although Neptune's discovery was considered a triumph there.

If Galileo discovered Neptune, and proved it was a planet (some other observations at the same time could help him out with that), the idea of celestial perfection is shattered. It relied on the idea of 7 planets in the sky, because 7 is the perfect number (7 days in a week, for example). The classical planets were Mercury, Venus, Moon, Mars, Jupiter, Saturn, and Sol. Neptune breaks that pattern, with a bit more force than the discovery of Jupiter's moons did.

Which in turn would probably mean a greater decline in mysticism amongst scientists? I'm thinking particularly of Newton here, although of course he will be butterflied. Would we perhaps have six colours making up the spectrum of colours? Just as arbitrary as the seven, I know, but since seven was built on mysticism whereas six at least has some visual basis it'd probably be more likely.
 
Well I know Neptune wouldn't probably be called Neptune in this case. It might be called Caelus (Uranus' Roman counterpart; Uranus is the only planet named after the Greek God and not the Roman one). The names of the elements uranium, neptunium and plutonium would also be different, since IOTL uranium was named shortly after Uranus was discovered. I wonder what Uranus would be called in this case? Maybe Neptune or Pluto? Then again the new planets might not be named after gods at all.
 
Well I know Neptune wouldn't probably be called Neptune in this case. It might be called Caelus (Uranus' Roman counterpart; Uranus is the only planet named after the Greek God and not the Roman one).

When Galileo discovered the Galilean moons, he originally named them for the four brothers of the Medici family as Cosimo Medici, Grand Duke of Tuscany was his patron.

Perhaps then ITTL, Galileo will break with the classical world and name the planet 'Cosimo' to ensure his patron's long-term support. If it sticks, Uranus may be named for the discoverer's patron or monarch (as it initially was IOTL).
 
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When Galileo discovered the Galilean moons, he originally named them for the four brothers of the Medici family as Cosimo Medici, Grand Duke of Tuscany was his patron.

Perhaps then ITTL, Galileo will break with the classical world and name the planet 'Cosimo' to ensure his patron's long-term support. If it sticks, Uranus may be named for the astronomer's patron or monarch (as it initially was IOTL).
Yeah I remember him naming them after the Medicis, and thought that if he did that with the Neptune, it would have been renamed (like the Galilean moons were). But it would be kinda cool if no one ever renamed them.
 
Yeah I remember him naming them after the Medicis, and thought that if he did that with the Neptune, it would have been renamed (like the Galilean moons were). But it would be kinda cool if no one ever renamed them.

Apparently the names of the moon were created in their current form by the German astronomer Simon Marius who claimed to have discovered the moons at the same time as Galileo. His names were just more popular.

But in the case of Neptune, it would harder for anyone else to claim concurrent discovery and bring forward alternate names. Whatever name choice Galileo made would have most likely stuck.
 
Which in turn would probably mean a greater decline in mysticism amongst scientists? I'm thinking particularly of Newton here, although of course he will be butterflied. Would we perhaps have six colours making up the spectrum of colours? Just as arbitrary as the seven, I know, but since seven was built on mysticism whereas six at least has some visual basis it'd probably be more likely.

Funny thing is, if we take light to have 6 colours, it's orange which should be removed. The primary colours of light are Red, Blue (Indigo) and Green, while the secondary colours are Cyan (Blue), Yellow and Magenta (Violet). Orange is a tertiary colour.
 
Funny thing is, if we take light to have 6 colours, it's orange which should be removed. The primary colours of light are Red, Blue (Indigo) and Green, while the secondary colours are Cyan (Blue), Yellow and Magenta (Violet). Orange is a tertiary colour.
Red, Orange, Yellow, Green, Blue, Violet. Those are the six colors of light. I think you're confusing the visible portion of the electromagnetic spectrum with the color display spectrum used by computer monitors and the like.
 
Light isn't composed of distinct colours you mix like paint, it's a continuum of frequencies of radiation. Any division into 6 or 7 colours is lines in the sand based on our own senses.
 
Light isn't composed of distinct colours you mix like paint, it's a continuum of frequencies of radiation. Any division into 6 or 7 colours is lines in the sand based on our own senses.
True, but my point was that these are the six recognized color groupings.
 
Red, Orange, Yellow, Green, Blue, Violet. Those are the six colors of light. I think you're confusing the visible portion of the electromagnetic spectrum with the color display spectrum used by computer monitors and the like.

If you really look, the Blue is a very distinct shade from the much darker indigo, which is itself different from the violet.
 
I thought that it was Uranus that he found, or was that Cassini? :confused:

No, it was Neptune. And, seeing as Galileo apparently knew of its motion, this should be a DBWI.

Now, say Neptune is decided a planet by Galileo. He'd need independent confirmation for people to pay attention. But if people do pay attention, maybe there is an earlier hunt for more planets? Earlier discovery of Uranus, Ceres?
 
If you really look, the Blue is a very distinct shade from the much darker indigo, which is itself different from the violet.
Most people I know consider indigo to be a deep shade of blue.

Either way, my point was that there are MORE than THREE colors. Are we done yet?
 
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