The Space Development Agency isn't interested in on-orbit refueling for its satellites, but it could drive down costs if it plans to contract with deorbiting services to mitigate risks on satellites at the end of their service lives, SDA Director Derek Tournear said today. SDA is scheduled to launch hundreds of satellites every two years for its Proliferated Warfighter Space Architecture of data transport and missile-tracking satellites in low-Earth orbit. Each satellite has an expected life of just five years...