watching us from high above

The European Space Agency, ESA, makes regular observations of planet Earth using its Venus Express probe, currently in orbit around Venus, I've just learned.

To Venus Express, Earth is just a single pixel on its detectors, much like an extrasolar planet would appear to some of our most advanced space telescopes. So the idea is to learn how to observe a living planet under such unfavourable circumstances. And then, of course apply this to the search for living planets elsewhere in the Universe.