## 4 Assessing EO Contribution to SDGs Indicators Using a Maturity Matrix Framework (MMF) Approach  
In 2017 and 2019, [PERSON] et al. [14; 15] presented analyses of published literature and other reports on the applicability of EO satellite data for SDG indicators using a structured MMF based on six premises (uncertainty assessment, directness, completeness, requirement for non-EO information, practicability, and cost-effectiveness analysis). The indicators were allocated an aggregate assessment score (entitled maturity Matrix Score (MMS)) based on the premises detailed in [15] and their overall potential for being populated with data from EO sources. Two versions of the MMF framework were produced and, using the latest version (MMF 2.0), applied to all 232 SDG indicators some 80 of them were determined to have some potential for being populated with data by EO. Of these, EO was found to provide weak support (MMS between 1 and 2) for 25 indicators, partial support (MMS values between 2 and 4) for 40 and strong support (MMS values between 4 and 5) for 15 indicators. The remaining 152 indicators had no evidence that EO could be used (at the time of the research). The SDG indicators have not been formally classified in terms of the three pillars of sustainability (economic, social, and environmental) by the IAEG-SDGs; there have been, perhaps surprisingly, few attempts to do this reported in the literature. Some exceptions are provided by [PERSON] and [PERSON] [168] on the SDGs, [PERSON] et al. [169] for the SDG targets and [PERSON] et al. [35] for the SDG indicators. Such a classification of indicators can be useful from a policy point of view [170] and can help to identify priorities for early action, understand implementation challenges, detect data gaps and indicate the trade-offs among SDGs [168]. A widely used taxonomy of indicators is based on the three pillars of sustainability that includes environmental, economic and social indicators (sometimes institutions are listed as a fourth dimension) [171]. Social indicators deal with broad categorical concerns of well-being (e.g., OECD's survey \"How is life?\" [172]), values (e.g., human values [173]), agency (demographic and health surveys [174] and inequality (often calculated via Gini coefficients) [175]). Economic indicators are statistics that allow an analysis of the economic performance of a country and are classified into two main categories: economic structure (e.g., gross domestic product (GDP), investment share in GDP, the balance of trade in goods and services) and consumption and production patterns (e.g., consumer price index (CPI), producer price index (PPI), household consumption, etc.) [171]. Environmental indicators are based on the four main Earth systems: atmosphere, hydrosphere, lithosphere, biosphere. Some environmental indicators are based on the human (anthropogenic) impact on the four main Earth spheres. The processes of human interaction and the Earth-system response to that interaction, such as pollution flows and natural resources stock (e.g., greenhouse gas emissions--CO\({}_{2}\), SO\({}_{\mathsf{x}}\), NO\({}_{\mathsf{x}}\), methane), use of water resources, river quality, wastewater treatment, land-use changes, protected areas, use of nitrogenous fertilizers, use of forest resources, trade in tropical wood, threatened species, fish catches, waste generation, municipal waste, industrial accidents). Lastly, partnership indicators measure the effectiveness of cooperation between two or more organisations [176]. The authors classified the SDG indicators into five main categories, as follows: social, economic, environmental, the comprehensive indicators--socio-economic and socio-environmental--and partnership; the results are presented in Figure 2. The assessment resulted in 94 social indicators that mainly related to social inclusion and inequality reduction (SDG 5 and SDG 10), poverty eradication (SDG 1), quality education (SDG 4), sustaining good health and well-being (SDG 3), and promoting peaceful and inclusive societies (SDG 16).