Using the boat model/perspective/telescope, wouldn't the Sun be the same?

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Using the boat model/perspective/telescope, wouldn't the Sun be the same?  After it's gone below the horizon due to perspective, couldn't we be able to see it again using a telescope?  Apologies if this has been asked already, I couldn't find it using search..
Edit: just found someone asking the same question but no good answers...
« Last Edit: August 15, 2017, 12:58:41 PM by bassfingerz »

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JackBlack

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If you were capable of bringing things which have gone past the horizon back into view with a telescope, then yes.

In reality you are not able to do that. Instead you can increase your height to bring it back into view.

What you can use a telescope for are things which are too small to resolve. The sun never reaches that point because of how far away it is and how big it is.

In a FE model, couldn't we use a telescope to see the sun no matter the time of day?  We can easily calculate the size we would need to see an object at the right distance.  When I have time I'll calculate the size refracting telescope to view a 32 mile diameter sun say 10,000 miles away.

Mike
Since it costs 1.82¢ to produce a penny, putting in your 2¢ if really worth 3.64¢.

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JackBlack

  • 21703
In a FE model, couldn't we use a telescope to see the sun no matter the time of day?  We can easily calculate the size we would need to see an object at the right distance.  When I have time I'll calculate the size refracting telescope to view a 32 mile diameter sun say 10,000 miles away.

Mike

How big do you want it to appear?

It should be 0.2 degrees, easily visible with the naked eye. So we shouldn't even need a telescope.

In a FE model, couldn't we use a telescope to see the sun no matter the time of day?  We can easily calculate the size we would need to see an object at the right distance.  When I have time I'll calculate the size refracting telescope to view a 32 mile diameter sun say 10,000 miles away.

Mike

How big do you want it to appear?

It should be 0.2 degrees, easily visible with the naked eye. So we shouldn't even need a telescope.
True but for arguments sake lets go the whole nine yards with this.

I just calculate the resolving power of my telescope and it works out to 0.89 arc seconds (NexStar 130).  I should be able to see the sun rather well at any time, day or night.  Although, at my location about 95 feet above sea level it might not work from here.

In theory it should work.

Mike
Since it costs 1.82¢ to produce a penny, putting in your 2¢ if really worth 3.64¢.

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rabinoz

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  • Real Earth Believer
Using the boat model/perspective/telescope, wouldn't the Sun be the same?  After it's gone below the horizon due to perspective, couldn't we be able to see it again using a telescope?  Apologies if this has been asked already, I couldn't find it using search..
Edit: just found someone asking the same question but no good answers...
Samuel Birley Rowbotham
Quote
EXAMINATION OF THE SO-CALLED "PROOFS" OF THE EARTH'S ROTUNDITY.--
WHY A SHIP'S HULL DISAPPEARS BEFORE THE MAST-HEAD.
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Before explaining the influence of perspective in causing-the hull of a ship to disappear first when outward bound, it is necessary to remove an error in its application, which artists and teachers have generally committed, and which if persisted in will not only prevent their giving, as it has hitherto done, absolutely correct representations of natural things, but also deprive them of the power to understand the cause of the lower part of any receding object disappearing to the eye before any higher portion--even though the surface on which it moves is admittedly and provably horizontal.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
"The range of the eye, or diameter of the field of vision, is
110°; consequently this is the largest angle under which an object can be seen. The range of vision is from 110° to 1°. . . . The smallest angle under which an object can be seen is upon an average, for different sights, the sixtieth part of a degree, or one minute in space; so that when an object is removed from the eye 3000 times its own diameter, it will only just be distinguishable; consequently the greatest distance at which we can behold an object like a shilling of an inch in diameter, is 3000 inches or 250 feet."


The above may be called the law of perspective. It may be given in more formal language, as the following:. when any object or any part thereof is so far removed that its greatest diameter subtends at the eye of the observer, an angle of one minute or less of a degree, it is no longer visible.

From: Samuel Birley Rowbotham, Earth is Not a Globe, CHAPTER XIV.
This is reasonably correct and it would lead to the vanishing point of the sun at about 3000 x 50 = 150,000 km.
So the sun, especially so extremely bright, should be easily visible even when the sun is at its furthest distance of about 32,000 km.
JRoa will undoubtedly claim the imperfect clarity of the atmoplane, but that doesn't hold water.

PS Rowbotham later "modifies" this when it doesn't fit observations and somehow limits vanising points further than the visible horizon.