Awesome shot of an F-14 going green over the Caribbean Sea November 1, 1990. Source: ChamorroBible
Fighter pilots call this phenomenon “going green”, commercial pilots and sailors call it “the green flash”. This happens when the the atmospheric conditions are correct to see beyond the horizon, and the curvature of the Earth’s atmosphere to the sun.
The atmosphere refracts light like a triangular prism hanging in sunlight. All the colors of the spectrum are split, and individually apparent. If you’ve ever had a prism hanging in a sunlit window, you have seen the full rainbow cast into the room. You can go over and put your finger in either the green light or the red light in the rainbow.
Fighter pilots can do that in their plane, by speeding up or slowing down to change it from red to green or vice versa. They can play with it at will, like changing a traffic light. By changing their speed, they can keep the Sun at the angle they want because they are able to travel faster than the Earth’s rotation at their exact Latitude. They can control the angle of the sun.
Commercial Pilots and Sailors cannot travel at the speed required to change the relative angle of the Sun. They know the phenomenon as “the green flash”, because it happens only momentarily due to the Earth’s rotation. Some people who can clearly see the horizon, say if they live on the ocean, may have seen this as well.