Suppose we want to reach the point on earth which in relative terms is exactly on the opposite end of the sphere we call earth (I know it is not an exact sphere).

We either dig vertically downwards, pass through the center of the earth and come out on the other end as it happens in the cartoon. But taking a more pragmatic approach means using air travel.

If we face North, we could either go East or West to get to the directly opposite point on earth which means traveling a distance of half the circumference of earth.

Now here is my question, since the earth is spinning, does it mean that if we fly in direction opposite to which the earth spins, we shall reach the other end quicker? why or why not?

If this is the case, the the opposite is true also i.e it will take longer for us to reach the other end if we travel in the direction of earth spin. Is this taken into consideration in actual flight routes?

  • 1
    $\begingroup$ Possible duplicates: physics.stackexchange.com/q/16390/2451 and links therein. $\endgroup$ – Qmechanic Mar 30 '15 at 0:17
  • $\begingroup$ When I hear "why or why not" my homework-detector goes off. Regardless, if you can fly above the atmosphere and fly west toward that point, you will get to it sooner because it is moving east. Of course, if it's on the equator, you could simply get above the atmosphere and wait 12 hours, and it will come to you (though that means you are traveling west with respect to the earth at about 1000 mph). Anyway, if you're flying in air, which is basically attached to the earth, the spin of the earth makes no difference. It's just a matter of wind. $\endgroup$ – Mike Dunlavey Mar 30 '15 at 14:05
  • $\begingroup$ This is not my homework but something I have wondered about for some time. You said that " if you're flying in air, which is basically attached to the earth". I thought that was not the case. Assuming that wind stops and we throw a balloon into the air, won't it stay stationary while the earth below it rotates? $\endgroup$ – quantum231 Mar 30 '15 at 23:03

There is a difference - but not exactly why you think. There are prevailing winds around the earth - these used to be called the "Trade Winds" because traders, knowing the direction of the wind, knew how best to navigate the globe. Basically, on the equator (in the tropics) they flow from east to west, and at higher latitudes they flow from west to east:

enter image description here

source of image

At higher altitudes you also have the jet stream - a strong west-to-east current that planes will sometimes use to fly much faster with the rotation of the earth:

enter image description here source of image

For planes, these winds make a significant difference in the time taken to fly long distances across the earth. And these winds are caused (indirectly) by the interaction of the rotation of the earth, and the sun.


Not the answer you're looking for? Browse other questions tagged or ask your own question.