Professor Nilton Renno's liquid water on Mars finding was named one of Discover magazine's top 100 science stories of 2009 and one of National Geographic's top 10 most popular space stories.

Renno, a professor in the Department of Atmospheric, Oceanic and Space Sciences and aco-investigator on the Mars Phoenix mission, analyzed photographsof droplets on the lander's leg and found proof that they are liquid water. That was the first time liquid water was detected and photographed outside the Earth. Read the press release. (A paper on the findings was published in the Oct. 14 Journal of Geophysical Research-Planets.)

While his findings were initially controversial, supporting evidence has mounted. Lab experiments by Renno and his colleagues have confirmed the conclusion of the photo analysis. (They were published Oct. 20 in Geophysical Research Letters.)

Now scientists are taking a new look at old data from other missions to explore whether certain phenomena could be explained by the presence of salty, liquid water.

Renno and his students Manish Mehta and Jasper Kok were involved in several aspects of the Phoenix mission. Phoenix studied the history of water on the Red Planet and looked for organic material—the building blocks of life.