Small satellites (smallsats) are miniaturized artificial satellites with a mass less than 500 kg used for communication, imaging, and other space applications.1 Recent advances in microtechnology have facilitated the development of smallsats equipped with compact, low mass, low-power-consumption sensors, which enable high-performance platforms with significant cost reductions compared to traditional satellite systems. The reduced payload of smallsats further decreases vehicle launch costs, which allows for deployment in constellations, where a group of satellites works in concert under shared control to achieve a particular mission.2 A constellation of satellites improves the resiliency of the overall system to degradation due to natural causes—such as radiation damage—or adversary attacks. They also allow for trade-offs in individual sensor performance (e.g., lower imaging resolution) in return for broader coverage and gap reduction.

Smallsats provide two primary enhancements to observation in space-based situational awareness relevant for both conventional and nuclear intelligence platforms: 1) advanced, low-cost sensing of in-orbit space objects and 2) persistent broad-coverage Earth imaging. The goal of a variety of smallsat systems is to increase the resiliency of satellite-based imaging systems while expanding planetary coverage. Hyperspectral and multispectral imaging modalities may be employed on smallsat platforms to enhance sensing capabilities.3 The performance of smallsats may be further augmented via high-resolution imaging capabilities and geospatial intelligence analytics.4 Technological advancements to expand the smallsat mission space through operational autonomy—in the form of intelligent interfaces and sensor tipping and cueing—are currently underway.5

  1. Smallsats are further classified by mass, where microsatellites are between 10 and 100 kg, nanosatellites are between 1 and 10 kg, and picosatellites have a mass between below 1 kg. Femtosatellites are an emerging smallsat class with a mass between 10 and 100 g, but current designs require a larger “mother satellite” for communications or launching and docking. See for example Timo Wekerle et al., “Status and Trends of Smallsats and Their Launch Vehicles—An Up-to-date Review,” Journal of Aerospace Technology and Management 9, no. 3, (July/Sept 2017), 269-286,; Daniel N. Baker and S.Pete Worden, “The Large Benefits of Small-Satellite Missions,” Eos Trans. AGU 89, no. 33 (2008),; Anil K. Maini and Varsha Agrawal, Satellite Technology: Principles and Applications (Chichester: John Wiley & Sons, 2014). 

  2. The number of satellites in a constellation typically ranges from 10s to 1000s. There is no lower or upper limit for the number of smallsats working in concert. 

  3. Hyperspectral imaging refers to a 2D spatial measurement with one spectral dimension, presented in the form of a data cube, or “hypercube.” Multispectral imaging refers to the ability to image in multiple bands using the same optical platform. For example, multispectral systems may provide data in the visible, near-infrared, and short-wave infrared spectral domains. 

  4. Darrell Etherington, “Satellogic raises $27M for affordable, high-resolution imaging satellites,” Tech Crunch, June 23, 2017,; National Research Council, Future U.S. Workforce for Geospatial Intelligence (Washington, D.C.: The National Academies Press, 2013),

  5. Becky Cudzilo, K.C. Foley, Chandler Smith, “The Ability of a Small Satellite Constellation to Tip and Cue Other Commercial Assets,” 26th Annual AIAA/USU Conference on Small Satellites, SSC12-IV-5, 2012,

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