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This article doesn’t say that penitentes appear only in the Andes, nor does it say in what part of the Andes they appear. Does the formation of penitentes require that the sun be nearly directly overhead for part of the day? Can penitentes form only near the equator?

Burton Loupee
Cedar Rapids, Iowa

Penitentes are also found in non-equatorial regions, says Meredith D. Betterton of the University of Colorado in Boulder. While the sun need not be directly overhead for the snow spikes to form, its midday position affects their tilt. For instance, penitentes far south of the equator lean more to the north than equatorial ones do. —P. Weiss