Originally posted by cikljamas
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What keeps these satellites in orbit? Isn't that practically the same question as this one: "how the earth is circumnavigated" (on a flat surface of the Earth)?
This is how:
In the following diagram, fig. 86, let N, represent the. northern centre, near to which lies the "magnetic pole." Then
the several arrows marked A, S, are all pointing northwards; and those marked E, W, are all due east and west. It is evident from the diagram, that A, S, are absolute directions--north and south; but that E, W, east and west, are only relative, that is they are directions at right angles to north and south. If it were not so then, taking the line N, A, S, as representing the meridian of Greenwich, and W, E, on that meridian as due east and west, on moving due west to the meridian 3, 4, N, it is evident that a vessel represented by the arrow 1, 2, would be at angle with the meridian 3, 4, N, much greater than 90 degrees, and if it continued to sail in the same straight line 2, 1, 5, it would get farther and farther away from the centre N, and therefore could never complete a path concentric with N. East and west, however, are directions relative to north and south. Hence, on a mariner arriving at the meridian 3, 4, N, he must of necessity turn the head of his vessel in the direction indicated by the arrow 6, 7, and thus continuing to keep the vessel's head square to the compass, or at right angles to north and south, he will at length arrive at 90 degrees of meridian from N, A, S, when the head of the vessel will be in the direction of E, W, 8. Continuing his course for 90 degrees more his path will be E, W, 9. The same course continued will in the next 90 degrees become E, W, 10, and on passing over another 90 degrees the ship will have arrived again at the meridian of Greenwich N, A, S, having then completed a circle.
This is how:
In the following diagram, fig. 86, let N, represent the. northern centre, near to which lies the "magnetic pole." Then
the several arrows marked A, S, are all pointing northwards; and those marked E, W, are all due east and west. It is evident from the diagram, that A, S, are absolute directions--north and south; but that E, W, east and west, are only relative, that is they are directions at right angles to north and south. If it were not so then, taking the line N, A, S, as representing the meridian of Greenwich, and W, E, on that meridian as due east and west, on moving due west to the meridian 3, 4, N, it is evident that a vessel represented by the arrow 1, 2, would be at angle with the meridian 3, 4, N, much greater than 90 degrees, and if it continued to sail in the same straight line 2, 1, 5, it would get farther and farther away from the centre N, and therefore could never complete a path concentric with N. East and west, however, are directions relative to north and south. Hence, on a mariner arriving at the meridian 3, 4, N, he must of necessity turn the head of his vessel in the direction indicated by the arrow 6, 7, and thus continuing to keep the vessel's head square to the compass, or at right angles to north and south, he will at length arrive at 90 degrees of meridian from N, A, S, when the head of the vessel will be in the direction of E, W, 8. Continuing his course for 90 degrees more his path will be E, W, 9. The same course continued will in the next 90 degrees become E, W, 10, and on passing over another 90 degrees the ship will have arrived again at the meridian of Greenwich N, A, S, having then completed a circle.
South Pole Star Trails
Explanation: No star dips below the horizon and the Sun never climbs above it in this remarkable image of 24 hour long star trails. Showing all the trails as complete circles, such an image could be achieved only from two places on planet Earth. This example was recorded during the course of May 1, 2012, the digital camera in a heated box on the roof of MAPO, the Martin A. Pomerantz Observatory at the South Pole. Directly overhead in the faint constellation Octans is the projection of Earth's rotational axis, the South Celestial Pole, at the center of all the star trail circles. Not so well placed as Polaris and the North Celestial Pole, the star leaving the small but still relatively bright circle around the South Celestial Pole is Beta Hydri. The inverted umbrella structure on the horizon at the right of the allsky field of view is the ground shield for the SPUD telescope. A shimmering apparition of the aurora australis also visited on this 24 hour night.
APOD: 2012 August 2 - South Pole Star Trails
Originally posted by aljhoa
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Are the following photos taken from the one sided Earth?
Star trails create arches over the horizon in a long-exposure picture of the night sky taken from Mount Kilimanjaro in Tanzania.
Space Photos This Week: Gravity Waves, Chicken Nebula
These star trails are centered on the celestial north pole. They were recorded in a time-lapse photograph over the course of about eight hours.
Open Course : Astronomy : Introduction : Lecture 2 : North Pole Star Trails Photo
Where on your "flat earth navigation chart" the counter rotating South Pole and North Pole star trails can be taken ?
Al
- irrelevantly as i sad 
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