Evidence for carbonate minerals has shown up on Mars in the eroded terrain of Nili Fossae. Formed in the presence of water, such areas might once have provided a suitable habitat for life. More at New Scientist.
Captain Randy Cramer claims to be an officer who has been given authorization to address the public on behalf of a covert "special section" of the United States Marine Corps. He joined guest host Jimmy Church (email) to discuss his 17-year tour of duty off-world on Mars, and his years serving aboard a secret space fleet.