Many of those characteristics are open to investigation with present spectroscopic techniques, or with modest improvements in their capabilities, but the results would be integrated over the entire planetary surface. For example, we may be able to detect oxygen and water vapor on an extrasolar planet, or perhaps the spectral signatures of complex organic molecules. But we would not be able to map the location on the planetary surfaces themselves.

High resolution optical interferometers in space could conceivably do this in the not-too-distance future. Interferometers fitted to terrestrial telescopes were able to map sunspots on nearby stars years ago. The technology could be much more effective in space.