Space Force Announces What Service Members Will Be Called ✖ The United States Armed Forces have soldiers, sailors, airmen, guardsmen, and Marines. Now, the latest branch of the military has determined what it's going to call those that fill its ranks. Henceforth, members of the United States Space Force will be known as Guardians. The branch's official Twitter account announced the news Friday afternoon, saying it consulted with space professionals and members of the general public for over a year before making the final decision. Furthermore, the Space Force also announced its motto as "Semper Supra," a Latin saying for "Always Above."