Continual increases in the spatial and temporal resolution of data freely available to researchers are being brought about by initiatives such as the Landsat, MODIS and Copernicus missions (Pettorelli, 2019 Williamson et al., 2019). Satellites are a vital tool for ecologists and conservationists to monitor ecosystem structure, composition and functioning (Pettorelli, Laurance, et al., 2014 Pettorelli, Safi, et al., 2014) track human activities and impacts on the natural world (Biermann et al., 2020 Kroodsma et al., 2018) and relay data from instruments deployed on animals (e.g., Barkley et al., 2019 Curnick & Feary, 2020 Doherty et al., 2017). Further, we argue that much remains to be done to ensure these new data products become accessible, equitable and sustainable. However, significant hardware and software developments are required before such technology is able to produce, process and handle reliable and cost-effective data, and the initial research and development costs still represent a major challenge. Combined, these benefits could significantly improve our ability to monitor threats to the environment as they unfold, while enhancing our understanding of animal ecology and ecosystem dynamics. In addition, SmallSats may serve as cost-effective research and development platforms for new components and products. Their greater flexibility and affordability may moreover enable the development of bespoke constellations for specific conservation and ecological applications, and provide greater interoperability with ground-based sensors, such as tracking devices and camera traps. They may cut access costs to end users, by reducing operational costs and bringing increased competition to the existing market. SmallSat constellations may yield higher resolutions than those that are currently available to scientists and practitioners, increasing opportunities to improve environmental-monitoring and animal-tracking capabilities. Here, we review the opportunities and challenges that such technology might afford in the field of conservation and ecology.

We are in the midst of a revolution in satellite technology, with the rapid development and advancement of small satellites (or SmallSats, i.e., satellites <180 kg).

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