shootingstar

Star coordinate systems
« on: January 13, 2019, 12:27:32 PM »
In astronomy we use a coordinate system called Right Ascension (RA) and declination (Dec) to describe a point in the sky. Call it the celestial coordinate system. RA is measured W-E according to the 24hr clock with 15 degrees of sky equating to 1h RA (15x24=360). Dec is measured by angular distance from the NCP (=90N declination) while the celestial equator is 0 degrees declination.


Needless to say declination circles in the northern hemisphere get smaller and smaller in radius until they come to the point of the NCP. Any stars which have a declination equal to the observers latitude or greater never set and so are called circumpolar.

The same applies in the southern hemisphere as well but how do we account for the declination circles getting smaller in the southern hemisphere because on a flat Earth, the latitude circles are still getting bigger as we pass south of the equator. To take a latitude at random, say 50 degrees south, those observers would see all the stars with a declination of -50 degrees or more (closer to the SCP) as circumpolar and so they would be visible all year round.
« Last Edit: January 13, 2019, 03:51:28 PM by shootingstar »

Jimmy McGill

Re: Star coordinate systems
« Reply #1 on: January 13, 2019, 08:21:00 PM »
I don’t see an explanation for this coming from any of the current flat earth models.

shootingstar

Re: Star coordinate systems
« Reply #2 on: January 14, 2019, 09:36:15 AM »
Well just to confirm what I mean here is a photo of star trails taken from Ecuador which straddles the equator. The VR image is particularly good I think. A lovely fireball is included just for good measure near the SCP.

http://sguisard.astrosurf.com/Pagim/From_pole_to_pole.html

As you would expect stars around the celestial equator are setting vertically w.r.t the horizon while the tail arcs are all concentric with the respective celestial poles. Polaris itself is not visible because it is simply too low on the northern horizon and there is some low altitude cloud in an case.

The pattern we see is easy to account for and exactly what we would expect to see if we live on a spherical Earth which is rotating on its N/S axis. However I cannot see how this could be accounted for by current FE models.

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Offline Stagiri

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Re: Star coordinate systems
« Reply #3 on: January 20, 2019, 07:08:53 PM »
I don’t see an explanation for this coming from any of the current flat earth models.

Well, Mr Bishop did (kinda) answer here.
Dr Rowbotham was accurate in his experiments.
How do you know without repeating them?
Because they don't need to be repeated, they were correct.

shootingstar

Re: Star coordinate systems
« Reply #4 on: January 21, 2019, 09:32:10 AM »
I have had a look through that thread. Seems a bit complicated to me.  A much simpler line of thought would be to just admit that the motions of the stars we see could be explained far more easily if the Earth was spherical.  That bipolar model is almost like bending a flat shape to make it round!

Re: Star coordinate systems
« Reply #5 on: January 22, 2019, 10:27:15 AM »
After reading Bishop's response, I'm left with more questions than answers.  It's unclear how two celestial poles would ever be seen from the surface of Flat Earth.  Personally I would love a more clear/explicit explanation of the forces governing apparent stellar movement in the Flat Earth model, because this is something about Flat Earth theory that has never been entirely clear to me.

A more simplistic way to put the question might be "Why is Polaris not visible in the southern hemi-"sphere?"  This is a well-documented phenomenon which seems impossible on Flat Earth; no matter where you are, you ought to have line-of-sight to Polaris.  I assume the Flat Earth explanation involves light "bending" in some way, but 1) that seems pretty well dismissed by this thread: https://forum.tfes.org/index.php?topic=6692.msg122178#msg122178 , and 2) I have as of yet seen no well-formulated mechanism from the FE community which would explain why the light bends, how much it bends, etc in such a way that it can be reconciled with what is observed.  On the Globe Earth, there is such a comprehensive theory, which involves the earth being spherical, stars being relatively stationary and distant, and not much else.  Because at this point in time GE theory is vastly more useful in explaining the motions of stars, it is obviously the superior scientific model with respect to stellar movement (not to say anything of "truth").

Anyone from the FE community want to offer up a comparable explanation for stellar motion?  I understand the FE camp does not have a "unified" theory in the same way the GE camp does, so it's totally possible a good explanation exists that I haven't come across yet.
« Last Edit: January 22, 2019, 10:30:58 AM by Physical_Copy »