NASA is undertaking a trio of closely related programs to continue human space exploration beyond low-Earth orbit. All three programs (SLS, Orion, and supporting ground systems) are working toward a launch readiness date of June 2020 for the first mission as reported in chapters 1 and 2.Chapter 3 reports on the development of a structural health monitoring (SHM) system for Space Launch System (SLS) vehicles based on acoustic emission (AE) or AE-like signals. Such a system will enhance SLS reliability by identifying the damage locations and type of damage when the damage is initiated. This SHM system would also lead to reduced maintenance costs by enabling ground support equipment to inspect only SLS elements or parts that are likely to be damaged.Preserving key U.S. national security and economic interests depends on the continued and widespread use of space-based systems. Satellites are as essential to military and intelligence operations as fighters, warships, and combat vehicles. Major portions of the global economy now rely on space systems; they facilitate modern banking, communications, agriculture, transportation, as well as a host of other commercial and civil activities as discussed in chapter 4.Chapter 5 provides background on the International Space Station (ISS), its governing international agreements, its planned service life, the ongoing commercialization of U.S. ISS access, and current commercial use of the ISS. Chapter 6 provides information on the James Webb Space Telescope, the cost cap, and the independent review.Congress may choose to approve, reject, or modify the FY2020 President’s budget request for National Security Space (NSS), which includes $14.1 billion for space launches, satellites, and other activities as reviewed in chapter 7. Congress has encouraged the growth of commercial space activities by requiring federal agencies to use private launch services and establishing offices to oversee commercial activity. As discussed in chapter 8 expanded commercial space activity has brought increasing attention to the use of U.S. airspace.

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