On April 17, the U.S. Air Force announced procurement plans for its next generation of missile warning satellites. Canceling further satellites launches for the Space Based Infrared System (SBIRS) constellation, the Air Force is instead transferring to a new program dubbed the Next Generation Overhead Persistent Infrared. Procurement is scheduled in five years, yet analysts are uncertain as to what the new constellation will look like. “We’re not ready to say what we think the right mix is,” said Dr. Will Roper, Assistant Secretary of the Air Force for Acquisition, Technology, and Logistics. “Part of moving to prototyping is acknowledging that you’ve got some experimentation and discovery to do. There are benefits to having things in LEO, there are benefits to having things in GEO, there are benefits to having things in highly elliptical orbits…We need things that work together to give us a resilient architecture.”