Due west @ 21:00 hours (02:00 UTC) @ my back yard (click on image for full sized pic)...
The greenish light on the right is a large yard light in my neighbor's yard (I hate it!)
Notice the position of the Sun shown by the app nearly off the right side of the screen about -10° or so below the horizon.
Notice also just the remnants of sky glow due to the Sun being BELOW the horizon. Now way to do that on a flat Earth. If the Earth was flat, the Sun would fade into the distance and look like Venus, which, if you're participating, you'll see in the western sky this evening. It's actually visible in my photo just above the tree on the right side of the image.
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