It is necessary to drop emotions in order to see what real benefit people can derive from visiting these [planets], Koptev told a news conference on Tuesday. “As far as I understand, even our U.S. colleagues have no answers to a number of questions,” Koptev said. A Mars mission will cost hundreds of billions of dollars, he said. It will not be easy for the United States to find money for it, given the country’s huge budget deficit.