Russia and the United States can collaborate in exploring Mars, Russian President Vladimir Putin told US Secretary of State Colin Powell in talks Monday. Congratulating the envoy on the US mission that has seen two probes land on the surface of the Red Planet in the past three weeks, Putin said that Russia “has noted with interest President (George W.) Bush’s ambitious plans for the conquest of Mars,” the Interfax news agency reported. “I believe that in this area there are things we can do together,” Putin said.