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What would happen if the world rotated in the opposite direction than it already does?
Question Date: 2012-10-27
Answer 1:

This is a very interesting question! One major difference that would affect our lives is that the sun would rise in the West and set in the East. As long as our planet still rotating the same way around the sun (counterclockwise if you are looking down on the North Pole), the seasons would still be the same.

Another big difference is that the wind and ocean “gyres” (the loops that wind and ocean currents move in) would be reversed. An important factor in our weather patterns is the “Coriolis Effect”. This phenomenon causes the winds at the equator to blow toward the west (opposite the direction of the earth’s spin at the equator). The winds loop around and blow from west to east at 30 degrees north and south of the equator. This is why the central United States gets “westerly” (from west to east) weather systems. This would be reversed if Earth were spinning the opposite direction.

Answer 2:

If the earth abruptly changed its rotational direction, probably many things we see every day would be destroyed. Skipping over the transition, however, an earth rotating in the opposite direction would, among other things, cause the sun, moon and stars to appear to rise in the west and set in the east.

This earth also would probably have much different climate and weather patterns than we have now. The world's weather systems move with the earth's rotation, so patterns on the continents would reverse. Southern California's mild, dry climate might change into Florida's hot, wet and stormy climate, for example. Ocean currents like the Gulf Stream would flow in opposite directions, probably upsetting things like the thermohaline circulation. Much of the North Atlantic would become much colder.

Since the pattern of the continents in relation to the currents and air flows would be changed, it is hard to say exactly what climate would exist where. Whole agricultural area would likely have to move or the farmers plant new crops, and many cities would grow in new favorable areas, while others would decline.

Answer 3:

The earth has what we call a pro-grade SPIN. That means that the direction of spin of Earth looking down from the North pole into the plane of the ecliptic is spin anti- clockwise --- THE SAME DIRECTION the earth ORBITS the Sun ( anti- clockwise).

So, if the earth was on retrograde rotation, then it would spin in opposite direction of earth revolution orbit around the Sun.

The main effect is that the stars , the Sun and planets of the night sky would rise in West and set in East; the seasonal variation would not be too much as they are governed mainly by earth’s orbit about Sun, and not its spin, although could have some other effects, such as tides raised on Earth due to Moon.

All planets in the Solar system orbit in the same direction as Earth around Sun. Most planets spin pro-grade but there are several notable exceptions such as Pluto, Uranus, and Venus among other objects in the Solar System.

It would be splendid to watch the Sun rise in the west and set in the east!!

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