Off-topic circumnavigating the earth in a mile or less [was Re: Significant digits in a float?]

[Ethan Furman]

On 04/30/2014 06:14 AM, Ethan Furman wrote:
> On 04/29/2014 03:51 PM, Chris Angelico wrote:
>> On Wed, Apr 30, 2014 at 8:42 AM, emile <emile at fenx.com> wrote:
>>> On 04/29/2014 01:16 PM, Adam Funk wrote:
>>>
>>>> "A man pitches his tent, walks 1 km south, walks 1 km east, kills a
>>>> bear, & walks 1 km north, where he's back at his tent.  What color is
>>>> the bear?"  ;-)
>>>
>>>
>>>  From how many locations on Earth can someone walk one mile south, one mile
>>> east, and one mile north and end up at their starting point?
>>
>> Any point where the mile east takes you an exact number of times
>> around the globe. So, anywhere exactly one mile north of that, which
>> is a number of circles not far from the south pole.
>
> It is my contention, completely unbacked by actual research, that if you find such a spot (heading a mile east takes you
> an integral number of times around the pole), that there is not enough Earth left to walk a mile north so that you could
> then turn-around a walk a mile south to get back to such a location.

Wow.  It's amazing how writing something down, wrongly (I originally had north and south reversed), correcting it, 
letting some time pass (enough to post the message so one can be properly embarrassed ;), and then rereading it later 
can make something so much clearer!

Or maybe it was the morning caffeine.  Hmmm.

At any rate, I withdraw my contention, it is clear to me now (at least until the caffeine wears off).

--
~Ethan~