[garygreen]

You can't explain this mathematically, and we have not seen a mathematical analysis by an astronomer using the distances and sizes in RET.

there's no math involved.  you're saying that a line isn't straight.  i'm saying it is.  you can use a line you know is straight (taut string) to demonstrate the fact of the matter for yourself.

stop arguing with thought experiments and cartoons.  you're better than that.  be an empiricist.

[Bobby Shafto]

You can't explain this mathematically, and we have not seen a mathematical analysis by an astronomer using the distances and sizes in RET. This is for the simple fact that this matter is unexpainable.

You demanded we do the math. Now you're saying it can't be explained mathematically?

The moon rotates in the z-axis with respect to earth. This is not the "flipping" of the moon that is explained in your wiki. This is not the 2° "shift" you argued, which is in the x- or y- axes. The moon "rolls" or "tilts" like the dial on a stove. And it's not constant or linear. It's fast sometimes. Slow other times. The way the sun illuminates the moon in this half-moon "not aligned" illusion you've introduced is related to that. 

You're objection that the moon doesn't "shift" more than 2° is addressing the wrong "shift." The direction of the sun's shine pattern on the moon is a function of the positions (angle + distance) of the moon AND the sun as viewed from earth. You've not done any math that incorporates the sun nor the angles involved. And when confronted with that, you revert to saying it can't be explained mathematically.

The perspective tilting explanation is fiction. If there was a real explanation, we would have a real document to point to -- not a stupid youtube video of some close range perspective tilting effects.

I know. I've looked all over for scholarly-type resources discussing this, but frankly, it's probably of no interest to astronomers who aren't concerned with defending whether or not the earth is a globe, spins, orbits the sun and is orbited by a moon.

This needs to be described using the real properties of the Round Earth System. I thought it was supposed to predict everything? Show it then. Show that the Round Earth System can cause this sort of tilting.

Okay. Challenge accepted.

[Bobby Shafto]

That's a really nice one. For me it shows, we're on a sphere.

I agree, and we've been having a long discussion about this observable "rolling" phenomenon of the moon on another thread that got booted to the Lounge. It's explicable in round earth. So far, no plausible explanation is provided for flat earth topography outside of hypothetical "electromagnetic accelerator" effect.

I think this terminator illusion is related, and instead of refuting that the sun illuminates the moon but that it does in a way that affirms we see it from a spherical earth.

[Tom Bishop]

Per the "you are working in the wrong axis" thing:

"SHOUT" all you want, but until you can grasp that you're working in the wrong axes, you're just going to remain frustrated, thinking that you're right and we're not getting it.

http://oi64.tinypic.com/2ed8ok6.jpg

As I stated in the assessment earlier, whether we imagine that the moon is traveling east to west, or north to south, or both, around the observer the perspective and any changes in its face and orientation is still going to be minimal.

Perspective isn't going to affect bodies at large distances with any large effect unless we also scale our observation points by a large distance. The diameter of the earth is tiny compared to the distance between the earth and the moon in RET, and the idea that we should be able to see vast changes in the angle of bodies is something that will need to be demonstrated.

Astronomers do care about this sort of thing. Over the years every time this topic comes up and the audience provides quotes from astronomical texts, we see that astronomers don't really know why, have trouble explaining it, and mumble something vague about celestial spheres.

[garygreen]

Astronomers do care about this sort of thing. Over the years every time this topic comes up and the audience provides quotes from astronomical texts, we see that astronomers don't really know why, have trouble explaining it, and mumble something vague about celestial spheres.

there isn't anything to explain.  you're just plain wrong that there's a problem to begin with.



you're saying that the line i've drawn won't point at the sun.  i'm telling you that it absolutely does, and you can demonstrate that it does by making your own straight line with a piece of string.  if you align one end of your string to be like the perpendicular line i've drawn on this moon, then you will find that the other end points at the sun.

you don't have to do any math.  you say this line doesn't point at the sun.  i say it does.  don't take my word for it.  see for yourself.

[Tom Bishop]

Astronomers do care about this sort of thing. Over the years every time this topic comes up and the audience provides quotes from astronomical texts, we see that astronomers don't really know why, have trouble explaining it, and mumble something vague about celestial spheres.

there isn't anything to explain.  you're just plain wrong that there's a problem to begin with.

https://i.imgur.com/AQpzxwI.png

you're saying that the line i've drawn won't point at the sun.  i'm telling you that it absolutely does, and you can demonstrate that it does by making your own straight line with a piece of string.  if you align one end of your string to be like the perpendicular line i've drawn on this moon, then you will find that the other end points at the sun.

you don't have to do any math.  you say this line doesn't point at the sun.  i say it does.  don't take my word for it.  see for yourself.

As I said, the only time the moon and sun is seen in the sky is when they are on opposite sides of the sky. Otherwise, when the moon gets too close to the sun it disappears.

A laser cannon pointed upwards into the sky is going to fire its laser beam into outer space. Its not going to wrap around to the horizon. The only way to get the laser beam to go to the opposite horizon is if you imagine it curving on the dome of the sky.

Your "string" experiment is bunk and lacking in explanatory power. You can find something pointing upwards and put a string to it and make any number of paths to the opposite horizon.

Find a panorama of the moon pointing into the sky above the sun and draw your string on it.



What you are trying to do is say that the sky is a dome and that if you make vertical triangles along the top of the image, cut it out with scissors, and paste it together in a domish way that there is a way to make (force) the moon to point at the sun. By manipulating it in this manner you can also force the moon to point at any number of objects on that opposite horizon.

This is not coherent. It is the "celestial sphere" explanation given by some astronomers; but this explanation falls flat with the slightest breeze.

- The sun and moon are not painted on a celestial sphere around the earth where straight lines become curved.
- The sun and moon exist in regular geometric space where an arrow will always point to the object it is pointing at, not in an entirely different direction.

There will need to be a more coherent explanation than this celestial sphere theory. In RET the observers aren't in a planetarium with lines projected on a screen above them that turn into curves. The observers are in regular space.

[ICanScienceThat]

Tom, you've inspired me. I'll do the math for you. I'll make you a video (100% troll free this time). But in return for all this effort, I'd like something from you. I'd like you to agree in advance that IF I can do the math you ask for, and IF the math shows that the RE model explains this illusion, you will publicly concede the point. You don't have to agree that the world is round, just admit that you made a mistake and the moon terminator illusion is perfectly explained by the standard heliocentric model.

What do you say? Sound fair enough?

[Tom Bishop]

If the distances/attributes of the Round Earth Model can explain the moon tilt illusion for gibbous and crescent moons, I have absolutely no problem admitting that. As I have seen, it cannot. It cannot explain it, and this is why the literature is so vague about the matter.

[ICanScienceThat]

If the distances/attributes of the Round Earth Model can explain the moon tilt illusion for gibbous and crescent moons, I have absolutely no problem admitting that. As I have seen, it cannot. It cannot explain it, and this is why the literature is so vague about the matter.

I don't know what you mean about "vague literature," but I'll get started on that. Will take some time... got work this weekend and family stuff.

Perhaps in the meantime, everyone might want to discuss the "police siren" hypothesis where the moon is internally lit by a rotating half-sphere? It sounds crazy and all, but could we actually come up with any sort of serious analysis of it?

Also, I thunk a thought. On the question of "earthshine" reflecting off of the unlit side of the moon... It seems likely that the amount of light the unlit side receives from the Earth would vary according to the Earth's "phase" as seen from the moon. We should be able to predict the Earth's phase and possibly we could measure the brightness of the unlit side of the moon. We could see if those correlate with each other at all. That would be a neat experiment and could provide valuable evidence.

[garygreen]

If the distances/attributes of the Round Earth Model can explain the moon tilt illusion for gibbous and crescent moons, I have absolutely no problem admitting that. As I have seen, it cannot. It cannot explain it, and this is why the literature is so vague about the matter.

the literature is silent on this problem because you are simply manufacturing the problem.  why would there be literature on a nonexistent problem?

As I said, the only time the moon and sun is seen in the sky is when they are on opposite sides of the sky. Otherwise, when the moon gets too close to the sun it disappears.

absurdly incorrect.  do a google search for "daytime moon."  you'll find many examples of crescent and gibbous moons.  how have you never seen a daytime crescent?

Find a panorama of the moon pointing into the sky above the sun and draw your string on it.

lol.  that you think this is a correct procedure demonstrates exactly how confused you are.  hint: straight lines in 3d space often stop being straight when you project them onto a 2d surface.  this is pretty much exactly the thing that i've been trying to tell you the whole time.  you're thinking of everything like an image.

What you are trying to do is say that the sky is a dome and that if you make vertical triangles along the top of the image, cut it out with scissors, and paste it together in a domish way that there is a way to make (force) the moon to point at the sun. By manipulating it in this manner you can also force the moon to point at any number of objects on that opposite horizon.

This is not coherent. It is the "celestial sphere" explanation given by some astronomers; but this explanation falls flat with the slightest breeze.

- The sun and moon are not painted on a celestial sphere around the earth where straight lines become curved.
- The sun and moon exist in regular geometric space where an arrow will always point to the object it is pointing at, not in an entirely different direction.

There will need to be a more coherent explanation than this celestial sphere theory. In RET the observers aren't in a planetarium with lines projected on a screen above them that turn into curves. The observers are in regular space.

what?  i've not said anything about triangles or celestial domes or anything else of the sort.

your argument is that the line perpendicular to the moon's terminator does not intersect the sun.  my argument is super simple: yes it does.  literally all you have to do demonstrate this fact to yourself is hold a taut string in front of your face.

instead you'd rather argue about cartoons and draw things on panoramas.  i don't get why.

[Tom Bishop]

It's not a camera effect. The eye sees it too.

Learn how a panorama works, Gary. A panorama is just a series of horizontally stitched images as the eye and camera sees it.

Here is another one:



Full size version is here: https://www.eso.org/public/images/potw1218a/

[Bobby Shafto]

Learn how a panorama works, Gary. A panorama is just a series of horizontally stitched images as the eye and camera sees it.

And in the stitching, lines that are straight in real life develop bends and angles because the camera focal point is rotated. 

Take that first panorama image you posted and draw lines across it that represent real life straight horizontal lines. No math. Just approximate. I'd like to see what you think you're seeing.

[inquisitive]

It's not a camera effect. The eye sees it too.

Learn how a panorama works, Gary. A panorama is just a series of horizontally stitched images as the eye and camera sees it.

Here is another one:



Full size version is here: https://www.eso.org/public/images/potw1218a/

We have enough problems with your use of the word perspective, let's not have the same with panorama.

[alfred1]

On the hand. A new moon  clearly shows that the edge of the  Earth is round.

[Bobby Shafto]

This needs to be described using the real properties of the Round Earth System. I thought it was supposed to predict everything? Show it then. Show that the Round Earth System can cause this sort of tilting.

Okay. Challenge accepted.

Using the Round Earth System ™ -based Stellarium, I found that a similar scenario will be occurring on September 17th 2018 right there in San Francisco on the waxing gibbous moon.

After sunset at 7:16PM the moon will be 10° east of due south, 30° in elevation. The sun will have set below the western horizon:

With simulated earthscape and atmosphere and a "straight" line from moon to sun:


Here without earthscape and atmosphere with position of sun in view:


Despite the sun appearing to be lower than the horizon, the moon's terminator will appear cocked slightly CCW of vertical:


Remember the "tilting" about the z-axis I was speaking about earlier?



Well, here is a time-lapse of the predicted orientation of the moon's phase on September 17th, from 4:15PM until midnight. (Sunset at 7:14PM at the 10-sec mark):

[rabinoz]

You can't explain this mathematically, and we have not seen a mathematical analysis by an astronomer using the distances and sizes in RET. This is for the simple fact that this matter is unexpainable.

The perspective tilting explanation is fiction. If there was a real explanation, we would have a real document to point to -- not a stupid youtube video of some close range perspective tilting effects.

There are real documents about the "The moon terminator illusion" but astronomers do not see it as an illusion.
They expect it as explained in this quote from the paper referenced below:

The moon tilt illusion is not described in astronomy textbooks because astronomers know that straight lines in object space become great circles on the celestial sphere.
Minnaert gives only a passing reference: “...the line connecting the horns of the moon, between its first quarter and full moon, for instance, does not appear to be
at all perpendicular to the direction from sun to moon; we apparently think of this direction as being a curved line. Fix this direction by stretching a piece of string taut in front of your eye; however unlikely it may have seemed to you at first you will now perceive that the condition of perpendicularity is satisfied”.

Note carefully, "Fix this direction by stretching a piece of string taut in front of your eye". In front of the eye or camera, not on the photo after it is taken.

This needs to be described using the real properties of the Round Earth System. I thought it was supposed to predict everything? Show it then. Show that the Round Earth System can cause this sort of tilting.

OK, but I do hope that your maths are better than mine: The Moon Tilt Illusion, Andrea K. Myers-Beaton and Alan L. Myers

[Tom Bishop]

Using the Round Earth System ™ -based Stellarium

This is false. Astronomy uses patterns and tables to predict the behavior of bodies in the sky and when the next occurrence will occur.

See the following Youtube video and the excel worksheet in the description.

https://www.youtube.com/watch?v=R4eDT8-73ZE

Rowbotham demonstrates the same sort of math in Earth Not a Globe at the end of the Lunar Eclipse chapter. It has nothing to do with a world model. It is all based on patterns.

[Tom Bishop]

OK, but I do hope that your maths are better than mine: The Moon Tilt Illusion, Andrea K. Myers-Beaton and Alan L. Myers

I suggest that everyone reads the full text of the article associated with Tom's isolated Moon picture (with the arrow)

http://www.seas.upenn.edu/~amyers/MoonPaper20June.pdf

Yes. Read that, and notice the following.

The number of times the author tries to explain the effect with the change of angles of something close up, such as the angled corners of the room or a building when you travel past it: numerous

The number of times the author actually uses the distance to the moon in any of her calculations: none

The number of times the author remarks how mysterious and hard to explain the issue is: several

[edby]

Astronomy uses patterns and tables to predict the behavior of bodies in the sky and when the next occurrence will occur.
[..]Rowbotham demonstrates the same sort of math in Earth Not a Globe at the end of the Lunar Eclipse chapter. It has nothing to do with a world model. It is all based on patterns.

The 'percent illumination' function, for example, uses the radius of the moon and the earth-moon distance. Why do you say 'nothing to do with a world model'?

[Tumeni]

As I said, the only time the moon and sun is seen in the sky is when they are on opposite sides of the sky. Otherwise, when the moon gets too close to the sun it disappears.

Wrong, wrong, wrong. In this example, the Moon was slightly West of South, and the Sun was climbing in the East. Roughly 90 degrees between them, as would be expected with a roughly Half Moon.

https://imgur.com/a/7DMpx3L


A laser cannon pointed upwards into the sky is going to fire its laser beam into outer space. Its not going to wrap around to the horizon. The only way to get the laser beam to go to the opposite horizon is if you imagine it curving on the dome of the sky.

But we're not talking about something "pointed upwards into the sky" from the ground. We're talking about an object some 240k miles distant, illuminated by a light source some 93 million miles distant. The line between those two IS a straight one, we're merely observing it from different angles, with differing inclinations with respect to that line.

It's a triangle. You, or any other earthbound observer, are at one point. The Sun and Moon are at the other two points. The side connecting sun and moon is the side opposite your point. The earthbound observer is not necessarily on the same plane as that line. The earthbound observer will, 99% of the time, be at an angle to that line, and will not perceive that line as a horizontal.

When looking at 2D diagrams of the interaction of earth, sun and moon, you always have to fill in the third dimension, or model it with scale model earth and moon. The latter would be the empiricist's way. Have you tried it?

Your "string" experiment is bunk and lacking in explanatory power. You can find something pointing upwards and put a string to it and make any number of paths to the opposite horizon.

...but not to a specific object. Nobody is suggesting pointing string at random toward the horizon.

There will need to be a more coherent explanation than this celestial sphere theory. In RET the observers aren't in a planetarium with lines projected on a screen above them that turn into curves. The observers are in regular space.

Coherent explanation already provided to you, in broadly the terms above, and repeated here (again).