The Aegis BMD uses the RIM-161 Standard Missile 3 mid-course interceptors and the RIM-156 Standard Extended Range Block IV (SM-2ER Block IV) terminal-phase interceptors developed by Raytheon. The Standard Missile 3 is a development of the SM2-ER Block IV, capable of intercepting ballistic missiles above the atmosphere (i.e., exo-atmospheric intercept) during the midcourse phase of a hostile ballistic missile's flight. The missile is launched from the MK 41 vertical launching system (VLS) of the warships. It receives in-flight target updates from the ship. The kinetic warhead (KW) is designed to destroy a ballistic missile's warhead with more than 130 megajoules of kinetic energy by colliding with it. The existing SM-3 Block IA version will be upgraded to SM-3 Block IB, SM-3 Block IIA and SM-3 Block IIB to counter future ballistic missile threats. The SM-2 Block IV can engage the ballistic missiles within the atmosphere (i.e., endoatmospheric intercept) in the terminal phase of a missile's trajectory. The missile carries a blast fragmentation warhead. The SM-2ER Block IV was further developed in a new extended range RIM-174 Standard ERAM (Standard Missile 6), which adds an active radar homing seeker.