1/18/2021 Memorandum on Space Policy Directive 7 | The White House (i) GPS is a key component of multiple sectors of United States critical infrastructure, as identified in Presidential Policy Directive-21 (PPD-21) of February 12, 2013 (Critical Infrastructure Security and Resilience) and stated in EO 13905. Cascading e ects from extended PNT service disruption or denial can adversely a ect all sectors. Autonomous vehicles on land, sea, and air have begun to rely on GPS for navigation, positional awareness, and other vehicle capabilities. Additionally, many information systems rely on the GPS timing signal to enable both fixed and mobile communications. An extended outage of GPS, or extended period of spoofed or manipulated GPS signals, could cause severe economic losses and put lives at risk. (ii) GPS remains critical to United States national security. Its applications are integrated into virtually every facet of United States military operations. United States and allied military forces will continue to equip and train for the responsible use of GPS and alternative PNT services to support mission operations. (iii) The widespread and growing dependence on GPS by military, civil, and commercial applications, systems, and infrastructure make the performance of many of these systems inherently vulnerable if disruption or manipulation of GPS signals were to occur. GPS users must plan for potential signal loss and take reasonable steps to verify or authenticate the integrity of the received GPS data and ranging signal, especially in applications where even small degradations can result in loss of life. In addition, whether designed for military capabilities or not, signals from PNT services and their augmentations provide inherent capabilities that may be used by adversaries, including enemy military forces and terrorist groups. (b) Space Applications. Applications for GPS now extend beyond Earth. The Terrestrial Service Volume of GPS, defined as the volume from the ground to an altitude of 3,000 kilometers, has become an integral component for space launch operations. Use of GPS is expanding into the Space Service Volume (SSV), which extends from 3,000 km to geosynchronous Earth orbit (GEO), despite reduced line-of-sight visibility and lower received signal power. Satellites rely https://www.whitehouse.gov/presidential-actions/memorandum-space-policy-directive-7/ 5/24