n the 1960s and 70s, the Mariner spacecrafts flew by Mars and took the first close-up pictures and tested temperature and atmosphere. From these missions, we learned that Mars was very cold (-123C at the south pole) and that the thin atmosphere was almost entirely carbon dioxide. Photos showed high volcanic mountains, giant craters and canyons, and deep valleys that may have formed by water which once flooded areas of the planet. In 1976, the Viking 1 and 2 spacecraft landed on Mars and took the first photos of its surface - more than 52,000 images! They showed "a forest of rocks" that were colored rusty red, and a yellowish pink sky. Soil samples taken by robotic arms searching for life were inconclusive.

Cool! But, I want to know about the recent stuff on Mars.