The Astronomy Behind the Legends of Planetos

[Lady Blizzardborn]

Indeed. I think it was Old Nan that described it as lasting a generation...

In terms of Westerosi traditions, this would be the time it takes for a woman to reach adulthood ~13 years. That number tends to pop up a lot around the lore of the long night...13th lord commander...reigning for 13 years...etc.

Except that the Long Night was not the same as Night's King's reign.

[Durran Durrandon]

Physically, it is hypothetically possible for a moon to be locked in Lagrange point 2 (look it up), in instead of being in orbit. That would make it permanently on the opposite side of a planet as the sun. It hasn't occurred anywhere in our solar system, so I imagine that it is utterly improbable, but it suppose, maybe. I think rather that it is just a writing cliche.

[Voice]

Except that the Long Night was not the same as Night's King's reign.

We don't know that, actually.

Edit: But, we do know he reigned during the long night. And, that his fall coincides with the end of the Long Night.

[White Ravens]

At first when I realized that, I also thought it was an oversight, or that I had missed a spotting in daylight. But I still haven't found one, and it's the repetition of moonrise as an hour in the night, a bit after sunset, that puzzles me.

...

Cersei lists several moments in the night, including moonrise AND moonset ! That would mean that every night, whatever the phase, the moon rises and sets during the night, at least during autumn and likely spring. And so at the antipodes of Westeros, the moon rises at the end of day, stays over the horizon all night, and sets in the beginning of the morning. I can't think how this could work without magic involved.

I have a "thing" about photographing the moon and, weather permitting I take pictures every night I can. The moon is often in the sky during daylight hours, but it is seldom noticeable, especially when high in the sky. Moonrises and moonsets are noticed and photographed more during the night because you readily see them happening. The full moon rises opposite the sun during sunset for example. By coincidence there was a full moon last night (or the night before depending on how you look at it.). Moonrise was half an hour before sunset four days ago, half an hour after sunset three days ago, 1 1/2 hour after sunset last night and will rise 2 1/2 hours after sunset tonight when I head down to the seaside with my camera and tripod to try to capture it. The moon will continue to rise later every night until it starts rising in the morning hours and in daylight. And on an on for 28 days until it is a full moon and rising opposite the setting sun again. Like Darkstar, the Moon is of the night, even though it is often present in the day.

Cause it's a story not an alternate reality. Most readers associate the moon with night. So he uses it that way to set the mood for a particular scene. What would describing a moon during daylight hours accomplish?

I agree. Most people in real life don't notice the moon during the day so why should characters in a book?

As for the possibility of a second, smaller moons orbiting Planetos in geosynchronous orbit, I doubt it. That would mean that it would always be above the same spot on the planet and would appear to go through crescent, gibbous, new moon and full moon phases every day because it orbits the planet every day rather than taking roughly a month like our moon does.

[LmL]

I can see Jon as the sun, but I don't see Rob, his cousin, as the moon eclipsing him. It doesn't work for me.

The point is the cousin part - it’s that he is shorter, and dead. He’s called a “fallen hero.” And Jon lived in his shadow. I don’t think Robb always represents the elf moon - just in this analogy. The idea that he is called a brother of Jon, the sun, indicates a similar nature... and I am speculating that the elf moon was a fire moon, like a smaller version of the sun (and darker).

Regardless, and admittedly I need to research geosynchronous moons, i think the elf moon WAS in eclipse position when it was struck by the comet, and so the “God’s Eye” image still fits.

[Frey family reunion]

Very interesting conversation. I do think astronomy plays a big part in the books. Snowfyre and I had a discussion a while back about some of the possible inspirations behind some of the character names and I suggested that GRRM may have partly been influenced in naming Meera after a variable, binary star, Mira. Mira apparently is one of the first variable stars discovered (star whose brightness fluctuates) and the astronomer who is credited with the discovery of Mira's variability is Johannes Holwarda (perhaps this led to GRRM naming Meera's father Howland and her brother Jojen). Snowfyre pointed out that Mira is located in the constellation, Cetus (a water dragon) and specifically located on the Neck of Cetus.

[Kingmonkey]

I believe George has said something about Planetos being like a slightly larger earth, so that would give it a bit more gravity, although I'm not sure how much that alters the equation. The fact that Pluto has a geosynchronous moon means Martin may well have heard about it and imagined this as part of his scenario, even if it's a tiny stretch in plausibility.

Planetos is definitely significantly larger than the Earth, but if it has a lower density it could have the same surface gravity.

How does a geosynchronous orbit affect the phases of the moon?

Wow. I'm no astrophysicist and have only the sketchiest understandings of orbital mechanics, but I have a suspicion that there would be a daily phase AND an annual phase overlaid. The "main" phase would be one day, because the requirement for a geostationary orbit is that it orbits the primary once per rotation of the primary (so that it remains in synch with the surface). That gives us a big problem for a lunar month.

However there's a difference between geosynchronous but and truly geostationary. The latter is a geosynchronous orbit -- orbiting above the equator, so over a fixed position, while non geostationary but geosynchronous orbit will move across the sky over the course of the day, returning to the same point in the sky at the same time of day. This would have to be a non-geostationary orbit or the moon wouldn't be able to rise and set. However, maybe with a very specific elliptical orbit the overlaid day and year phases might create a visible month phase? This is way beyond my knowledge tbh.

If the remaining moon is in such an orbit, what does that say about the first one? If it was between sun and Planetos, it would be harder to see, wouldn't it? Maybe impossible? The could open the window for a remaining corpse of a moon. It might also explain why Planetos wasn't running into a large debris field - the debris field, such as it was, would have an orbit just inside Planetos' orbit, like a black band around the sun. There's a bit of evidence for something like this, actually... *cough*

I think to be permanently in daylight, the moon would have to be at a Lagrange point rather than a geostationary orbit. Technically possible that a moon could be knocked out of orbit and end up at the Lagrange point, but unlikely.

If it was a debris in a closer orbit to the sun, it would create a band, but I think it would take an EXTREMELY long time to do that. You'd get a small diffuse sphere of rubble first.

If both moons were in a geosynchronous orbit, we would never have eclipses, am I right? I do think there is talk about keeping record of eclipses, although if will now go do a woes search of every book for "eclipse" to find out.

One last thought: if the elf moon was smaller, and possibly black or dark, when it was in a solar eclipse formation, it probably wouldn't cover the entire sun - but it might appear as a black iris in the middle of the solar eye. Is that the origin of the term "God's Eye?" I have a feeling it might.

I think you'd get an eclipse twice a year at the solstices, but I'm really not sure. Though if you had a true geostationary orbit, which is equatorial, wouldn't you see an eclipse once every day if you're at the equator? Not sure.

The reason our eclipses are the way they are is because by coincidence the apparent size in the sky of the sun and moon are very similar. A smaller moon would indeed only cover a part of the sun. In fact there are transits of Venus and Mercury, where those two planets, being between us and the sun, go in front of the disk of the sun for us. They are way too small and distant to eclipse the sun properly, you need a telescope to make out the black spot. However there's no requirement for the moon to be dark, a brilliant white moon is still going to look black against the sun.

[LmL]

Very interesting conversation. I do think astronomy plays a big part in the books. Snowfyre and I had a discussion a while back about some of the possible inspirations behind some of the character names and I suggested that GRRM may have partly been influenced in naming Meera after a variable, binary star, Mira. Mira apparently is one of the first variable stars discovered (star whose brightness fluctuates) and the astronomer who is credited with the discovery of Mira's variability is Johannes Holwarda (perhaps this led to GRRM naming Meera's father Howland and her brother Jojen). Snowfyre pointed out that Mira is located in the constellation, Cetus (a water dragon) and specifically located on the Neck of Cetus.

That’s fantastic stuff Frey family reunion! The water dragon thing gives me a hint / corroboration about an idea I have in regards to sea dragons.” Seems pretty obvious he’s into astronomy. That’s a great example. Give me the link to your thread, I will mention it in a future section as a corroboration of the general principle of George using astronomy, and add a link to it.

[LmL]

Kingmonkey: I realize I was getting confused between ‘geosynchronous’ and ‘geostationary.’ I’m just going to do some research and see what makes the most sense. I think it’s clear the remaining moon orbits normally, my question was really about the old one.

[Frey family reunion]

That’s fantastic stuff Frey family reunion! The water dragon thing gives me a hint / corroboration about an idea I have in regards to sea dragons.” Seems pretty obvious he’s into astronomy. That’s a great example. Give me the link to your thread, I will mention it in a future section as a corroboration of the general principle of George using astronomy, and add a link to it.

Sorry no link, it was all through pms. For some reason the idea of binary stars seemed significant to me at the time, and I kind of wondered if the blue star eyed white walkers might have been a bit of a nod towards another binary star, Sirius, "the dog star". Sirius is also a blue shift star. And located on the Constellation, Canus Major which called to mind Symeon Star Eyes watching the two hell hounds fighting (Canus Major and Minor?)

I've always thought that Ignatius Donnelly's Ragnarok: an Age of Fire and Gravel might be a possible inspiration. It speculates that a lot of different cultures' mythologies were influenced by a near comet strike which caused widespread fires, floods, poisonous gases, and unusually vicious and prolonged winters. Check out the wiki entry on it: http://en.wikipedia.org/wiki/Ragnarok:_The_Age_of_Fire_and_Gravel

[LmL]

Sorry no link, it was all through pms. For some reason the idea of binary stars seemed significant to me at the time, and I kind of wondered if the blue star eyed white walkers might have been a bit of a nod towards another binary star, Sirius, "the dog star". Sirius is also a blue shift star. And located on the Constellation, Canus Major which called to mind Symeon Star Eyes watching the two hell hounds fighting (Canus Major and Minor?)

I've always thought that Ignatius Donnelly's Ragnarok: an Age of Fire and Gravel might be a possible inspiration. It speculates that a lot of different cultures' mythologies were influenced by a near comet strike which caused widespread fires, floods, poisonous gases, and unusually vicious and prolonged winters. Check out the wiki entry on it: http://en.wikipedia.org/wiki/Ragnarok:_The_Age_of_Fire_and_Gravel

I enjoyed Donnelys book about Atlantis immensely. I'll check that one out.

[Voice]

Kingmonkey: I realize I was getting confused between ‘geosynchronous’ and ‘geostationary.’ I’m just going to do some research and see what makes the most sense. I think it’s clear the remaining moon orbits normally, my question was really about the old one.

I don't.

If the moon is only in the sky at night, it isn't orbiting normally. It is almost as if the moon is frozen in the background of stars. Planetos itself might be as well. The varying length of day/night could easily be explained by the wobble of the planet's axis. Perhaps the seasons ceased being physical, and started being magical, when Planetos ceased its revolution around the sun...

[LmL]

I don't.

If the moon is only in the sky at night, it isn't orbiting normally. It is almost as if the moon is frozen in the background of stars. Planetos itself might be as well. The varying length of day/night could easily be explained by the wobble of the planet's axis. Perhaps the seasons ceased being physical, and started being magical, when Planetos ceased its revolution around the sun...

This from Waters Gate:

The fact that it takes 30 days for the moon to revolve Planetos is rather easy to prove. It's in the Arya chapters. Arya meets the kindly man every 30 days at the house of black and white when the moon is dark. I am to lazy to bury up the exact passage in the books right now but you can deduce it with 100% certainty from the books.

And do take note of the FM's worship of the moon and it's phases. And the perculiarity that they have a certain affinity with a "darkened moon".

If it was geosynchronous, it would go through all the phases every night. Unless I am missing something.

[Voice]

This from Waters Gate:

If it was geosynchronous, it would go through all the phases every night. Unless I am missing something.

That still doesn't add up.

While the moon on Planetos does indeed exhibit phases, for such phases to be caused by a normal orbit, would completely ensure they occur at different times of day, during both day and night.

Case in point, a waxing crescent moon is only observable in the afternoon, and briefly post-dusk. On the other side of the cycle, the final waning crescent moon is only visible near dawn. "When the moon is dark" occurs because the moon is between planet and sun, as the side of the moon that is illuminated is on the sun's side, while the dark side of the moon faces the planet.

[Durran Durrandon]

"But, while he was shouting, he saw with suprise

That the moon of the evening was starting to rise

Up over his head in the darkening skies.

"What's THAT?" snorted Yertle. "Say, what IS that thing

That dares to be higher than Yertle the King?"

- Yertle the Turtle, Dr. Seuss

You see here we we see the moon just rising just as the sun set, as indicated by the darkening sky. Does this mean that the moon in Dr. Seuss' universe is locked in a fixed position on the opposite side of the planet as the sun? Or did he just use a common trope?

[Voice]

"But, while he was shouting, he saw with suprise

That the moon of the evening was starting to rise

Up over his head in the darkening skies.

"What's THAT?" snorted Yertle. "Say, what IS that thing

That dares to be higher than Yertle the King?"

- Yertle the Turtle, Dr. Seuss

You see here we we see the moon just rising just as the sun set, as indicated by the darkening sky. Does this mean that the moon in Dr. Seuss' universe is locked in a fixed position on the opposite side of the planet as the sun? Or did he just use a common trope?

Not at all, in fact Dr. Seuss' version makes far more sense than GRRM's, as the moon is visible "in the darkening skies" rather than "at night." The moon will rise as dusk approaches (particularly first quarter moons), because the earth is rotating and the horizon moves toward the area of space in which the moon is lit (lit by the sun, which is just below the horizon for a first quarter moon). This is why the moon often appears to be "laying down" as it rises. It is we who are sideways, with the sun below our feet.

[LmL]

Dr. Seuss is familiar with Morningstar deities, it would seem. ;)

VotFM, do you disagree with Waters Gate that the moon has been observed to go through its phases every 30 days?

[Voice]

Dr. Seuss is familiar with Morningstar deities, it would seem. ;)

VotFM, do you disagree with Waters Gate that the moon has been observed to go through its phases every 30 days?

Not at all, it's come up before, though I think the number of days was less than 30 when it was calculated in another thread. What I disagree with is the idea that the orbit is in anyway "normal." A normal orbit requires some observances of the moon in morning, day, and late afternoon hours... rather than only at night.

[LmL]

Not at all, it's come up before, though I think the number of days was less than 30 when it was calculated in another thread. What I disagree with is the idea that the orbit is in anyway "normal." A normal orbit requires some observances of the moon in morning, day, and late afternoon hours... rather than only at night.

Ok, so I guess I didn't mean to say "normal" as in "just like ours." I meant only that it is not in a geosynchronous orbit, because then the all phases of the moon would occur each day... Again, unless I am missing something. I am no more than an amateur astronomer, with a very incomplete knowledge of astronomy compared to someone who went to college for it. I may be misunderstanding, so correct me if I am wrong, I'd like to figure this out.

[Voice]

In case you haven't seen it, this timeline is pretty awesome....gives lunar cycles and stuff...