Gallery: The Six Places on Earth That Most Resemble Other Planets

The Haughton Mars Project tested equipment and people bound for Mars - at a much more convenient location. Devon Island, Canada, is the world's largest uninhabited island, home to the Haughton crater, which is a 12-mile diameter impact area where a meteorite hit Earth 23 million years ago. The rocky Arctic polar desert setting, geologic features and biological attributes of the site offer unique insights into the possible evolution of Mars, say the researchers - in particular, the history of water and of past climates on Mars, the effects of impacts on Earth and on other planets, and the possibilities and limits of life in extreme environments. While no environment can come close to Mars' extremes in minimum temperature, dryness, low atmospheric pressure and harsh radiation conditions, the Arctic desert is just about as close as scientists can get.

Pictured: Dr. Jeff Jones of NASA Johnson Space Center tests a space suit prototype in a late-night simulation.