Skip to main content

You are not logged in. Your edit will be placed in a queue until it is peer reviewed.

We welcome edits that make the post easier to understand and more valuable for readers. Because community members review edits, please try to make the post substantially better than how you found it, for example, by fixing grammar or adding additional resources and hyperlinks.

1
  • I suppose it's not that easy. Think of the shape of the Earth: more or less an ellipsoid, but slightly egg shaped (not 100% symmetric up or down the equator). Try figuring it out with a perfect sphere first Commented Dec 1, 2015 at 13:39