Wednesday, July 9, 2008


Quick! What is the highest place on earth?

If you say Mt. Everest, you're kinda wrong. Mt. Everest is highest above sea level. However, the earth isn't a perfect sphere, which means that the distance from the center of the earth to the surface is greatest at the equator. This distance isn't entirely trivial...6357 kilometers from the center to the poles, and 6384 kms from the center to the top of Mt. Chimborazo in Ecuador. A basketball with these proportions would probably bounce a tad unpredictably.

From this perspective, Everest is 2.4 kms lower than Chimborazo! Furthermore, the Mariana Trench is quite a bit "higher" than some areas on the ocean floor near the North Pole. I say "some areas" because scientists, believe it or not, have yet to pinpoint the exact spot on the earth's crust that is closest to the center.

For the weight-conscious, Chimborazo is also the world's best place to stand on a scale. If my numbers are right, you'd weigh about 1% less on Chimborazo than at the poles. Not noticeable, though I wonder if somebody with a highly trained sense of gravity (a juggler? a high jumper?) would perceive a difference. The greatest high jump in history occurred in Salamanca, Spain at 40° latitude, and the second highest actually occurred in Stockholm (59°), which argues against any significant effect.

The diminished pull of gravity, however, is significant enough that it makes good sense to launch large rockets near the equator.

There was a time a couple hundred years ago when Europeans believed Chimborazo to be the highest point on earth! They were correct for the wrong reasons. I presume they arrived at this judgement via triangulation, just as they later arrived at a measurement for Everest, with sea-level as a reference point. Alexander Humboldt (of Humboldt Bay and Humboldt Current fame) attempted the summit in 1802.

Three other peaks are actually further from the center of the earth than Everest: Huascaran, Cotopaxi, and Kilimanjaro. Given the difficulties in making precise measurements from the absolute center of the earth, there's some debate, in fact, whether Huascaran might actually be a tad taller than Chimborazo. For me, all this ambiguity points to the illusoriness of pursuing the world's "highest" summit. Given the relative ease of climbing Chimborazo, one wonders if some anonymous, bored Incan nomad (did Incans have nomads?) scampered up the peak 1,000 years ago, leaving the goats to fend for themselves.

Another item to add to the "things to do before you croak" list. It'll go somewhere above "hear the roaring sands" and below "see a really intense aurora".

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