<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Lol, just wondering if the sun could rise from west to east on earth ;o. <br /> Posted by TahaSiddiqui</DIV></p><p>Barring a (possibly literally) earth-shattering calamity (or the aforementioned SR-71 or similar very fast transport), it can't happen on Earth. But it <em>can</em> happen on other worlds.</p><p>All you need is a planet that rotates retrograde (backwards). Venus is one such world. If you could see through the smog and clouds, you'd see the sun rise in the west. 243 Earth days later, you'd see it set in the east.</p><p>There are stranger worlds in terms of rotational oddities. Mercury is prograde, but because it is so close to the Sun, and because of the relatively high eccentricity of its orbit, the Sun would appear to grow and shrink, and even occasionally reverse direction in the sky.</p><p>Uranus and Pluto both have extreme tilts to their rotational axes. In the case of Uranus, it's just over 90 degrees, so there are long periods for each hemisphere when the Sun doesn't rise at all. </p> <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em> -- The Tenth Doctor, "Blink"</font></p> </div>