• The volcano ? Chimborazo, its summit being the point on the Earth’s surface that is farthest from the Earth’s center and closest to the sun.
• The scientists ? Alexander von Humboldt and Aimé Bonpland.
• The year ? 1802, in the middle of their 5-year American expedition.
• The country ? Ecuador, in the Cordillera Occidental range of the Andes.

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Humboldt and Bonpland at the foot of the Chimborazo ?