PHOTO GALLERY | Leadership experts share their picks on the year’s top reads.
"Great By Choice" by Jim Collins and Morten T. HansenMichael Useem, director of the Center for Leadership and Change Management at the University of Pennsylvania's Wharton School, picked Jim Collins and Morten T. Hansen's "Great By Choice" as the best leadership book of 2011. Courtesy of Fortier Public Relations
NASA tried one last time to contact its record-setting Mars rover Opportunity, but declared it dead on Feb. 13, 2019, 15 years after arriving at the Red Planet. The solar-powered rover has been silent for eight months, victim of one of the most intense dust storms in decades.