The U.S space force is planning to Develop a space ride to carry small satellites and hosted payloads by the end of 2021. It will Develop a common adapter equipped with a propulsion system. The space force’s Space Test Program mission later this year will launch Long Duration Propulsive ESPA (LDPE) payload on the Atlas 5. The LDPE utilizes EELV Secondary Payload Adapter (ESPA).
ESPA, the adapter, is used for secondary payloads of small satellites. The ESPA is equipped with certain power and propulsion systems to launch successfully and carry payloads to the final orbits. Space and Missile Systems Center (SMC) aims to use the LDPE to carrying out the next planned missions of small satellites.
Currently, SMC is Develop Tetra, which is a series of small satellites. Each satellite will have the capability to host a range of payloads. Millennium Space Systems is the first manufacturer of Tetra satellites. It is scheduled to launch by October on SpaceX Falcon Heavy. The Tetra 3 and 4 satellites are built by York Space Systems. The missions these satellites will carry are not yet defined.