Two U.S. astronauts came home yesterday after spending nearly 200 days at the international space station, and it wasn't a U.S. spacecraft they returned in. They had to hitch a ride home with Russia. With the U.S. putting in question its geopolitical and economic alliances, Yahoo Finance talked to Neil deGrasse Tyson, well-known astrophysicist and author of the new book, Accessory to War, the Unspoken Alliance Between Astrophysics and the Military about the relationship between science and the military, and the U.S. getting left behind in the race for space. Yahoo Finance's Seana Smith and Dion Rabouin sat down with the famous scientist.