Outer Space

Today, humanity faces a plethora of challenges related to water. As an effect of drought, some regions’ populations see their water reserves gradually but surely emptying. Around 40 per cent of the world’s population is affected by water scarcity. Elsewhere, people suffer from flash floods, rising sea levels or extreme weather. Rising sea levels affect agriculture, livelihoods, biodiversity and coastal habitats that are home to 900 million people. The next step in fully tapping the potential of space assets to improve life on Earth is to democratize access to these transformative tools and scale their application to benefit communities worldwide. In a world riddled with inequalities, we cannot let the space sector become yet another field of persistent gaps among and within countries. To advance access to space solutions for addressing water challenges, the United Nations Office for Outer Space Affairs (UNOOSA) launched a dedicated Space4Water project at the beginning of the Water Action Decade in 2018. The Project, with its three pillars of conference series, web portal and community building, addresses knowledge exchange between scientific communities, policymakers, intergovernmental organizations, the private sector, civil society and the public. Through these efforts, we are strengthening communities, amplifying the voices of Indigenous communities, connecting them with professionals with the technical background to address their issues, and sharing a vast range of learning opportunities at different knowledge levels.

This report has been prepared following the Day of 8 Billion, designated by the United Nations as the day when the world population reached 8 billion people, to showcase how space technologies and its synergies can help to tackle the challenges of the world increasing population and complex societies while ensuring sustainable development and bolster resilience, leveraging the guidance of the “Space2030” Agenda and supporting the implementation of the global agendas. The present report has been conceived within the cooperation agreement signed between UNOOSA and EUSPA with the goal of promoting how the use of space technology, data and services can contribute to achieving sustainable development in the context of an 8 billion world, and how the “Space2030” Agenda establishes the priorities of Member States for the space community.

Global navigation satellite systems (GNSS), which were originally designed to provide positioning, velocity, and timing services for terrestrial users, are now increasingly utilized for autonomous navigation in space as well. Historically, most space users have been located at low altitudes, where GNSS signal reception is similar to that on the ground. More recently, however, users are relying on these signals at high altitudes, near to or above the GNSS constellations themselves. The availability and performance of GNSS signals at high altitude is documented as the GNSS Space Service Volume (SSV). While different definitions of the SSV exist and may continue to exist for the different service providers, within the context of this booklet it is defined as the region of space between 3,000 km and 36,000 km above the Earth’s surface, which is the geostationary altitude. For space users located at low altitudes (below 3,000 km), the GNSS signal reception is similar to that for terrestrial users and can be conservatively derived from the results presented for the lower SSV in this booklet.