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To: Campion

Come on, look at the animation. The moon is moving at the earth’s rotational velocity. That means the moon will orbit the earth in 24 hours. That’s called a geostationary orbit, aka a geosynchronous equatorial orbit (GEO). A GEO is a circular orbit 22,236 miles in altitude above Earth’s Equator.


49 posted on 02/07/2022 1:39:30 PM PST by ProtectOurFreedom (If truckers quit their jobs, society would collapse. If politicians quit their jobs...HALLELUJAH!)
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To: ProtectOurFreedom
That's really what you see when you look at that? Seriously? The earth is rotating close to halfway around. In the same time the moon is passing across the field of view. The width of that field of view is not anywhere close to half of the moon's orbit around earth.

A little simple trigonometry will show that. Imagine the earth (8000 miles wide) is the base of an isoceles triangle whose height is the distance from earth to the satellite (872600 miles). Then the angle that the earth subtends from the satellite's POV is 2 * arctan(4000 / 872600) or 0.5253 degrees. That's right, the earth in the picture takes up barely 1/2 of a degree of the satellite's field of view.

Do the same thing with the moon's orbit. The moon's average distance from earth is 238,600 miles. 2 * arctan(238600 / 872600) is 30.6 degrees. So the earth (which is a little smaller than the frame size) would be 0.525 degrees of the satellite's field of view, while the moon's orbit end-to-end would be 30.6 degrees.

So while a point on the earth is moving (about) 0.525 degrees across the satellite's field of view, and the moon is moving only a little more than that, you're telling me that they're moving at the same rotational velocity? How is that remotely possible, since that point on the earth is rotating about 180 degrees in about 1/2 degree of apparent motion, and the moon is moving just a bit more than that, say 1 degree of apparent motion, but for the moon to rotate 180 degrees around the earth, it would need to move more than 30 degrees of apparent motion?

54 posted on 02/07/2022 3:32:56 PM PST by Campion (NO Wag-the-Dog WARS for Big Guy Brandon's 10%)
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To: ProtectOurFreedom

I think you’re assuming (subconsciously), because the image is flat and 2-D, that the moon is fairly close to the earth’s surface compared to the distance of the satellite. But it’s not: the distance from the satellite to the moon, when the moon is directly between the satellite and the earth, is less than 3/4ths the distance from the satellite to the earth.


56 posted on 02/07/2022 3:40:22 PM PST by Campion (NO Wag-the-Dog WARS for Big Guy Brandon's 10%)
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