Given this paragraph, extract a list of names that are playable by the user of this game.

Context: During the single-player campaign, the player controls five different characters from a first-person perspective. The player primarily controls Sergeant Gary "Roach" Sanderson, a British member of an international special forces unit named Task Force 141. In addition to Roach, the player will also assume control of Private First Class Joseph Allen and Private James Ramirez of the U.S. Army's 1st Battalion/75th Ranger Regiment. The now Captain John "Soap" MacTavish serves as a senior member of Task Force 141, acting as Roach's superior officer and becomes the playable character in the final three missions of the game. Lastly, the player briefly assumes the role of an astronaut stationed on the International Space Station during the height of the war between the United States and Russia.

The game's non-playable characters feature prominently in the story: For Task Force 141, Lieutenant Simon "Ghost" Riley, who conceals his face with a skull print balaclava serves as Soap's second in command. For the United States Army Rangers, Sergeant Foley, along with his subordinate, Corporal Dunn, is initially Joseph Allen's squad leader, and becomes James Ramirez's squad leader later in the story. Lieutenant General Shepherd is the commander of the United States Army Rangers and Task Force 141. Other supporting characters returning from Call of Duty 4 include Captain John Price, MacTavish's former commanding officer in the British Special Air Service who was imprisoned in Russia, and Russian informant turned mercenary pilot "Nikolai".

Answer: 1. Sergeant Gary "Roach" Sanderson
2. Joseph Allen
3. James Ramirez
4. John "Soap" MacTavish
5. An unnamed astronaut