# An Overview of CubeSat Missions and Applications
## 3 CubeSats as Earth Observation and Earth Science Platforms
### The Role of CubeSats in Earth Observation Missions
Among notable examples of COTS imaging solutions for the visible and NIR regions of the electromagnetic spectrum that are available as of 2025 are the Simera Sense (Leuven, Belgium) xScape50, xScape100, and xScape200 series of optical imagers which can provide a Ground Sampling Distance (GSD) of 30 m, 4.75 m, and 1.5 m, respectively, at an altitude of 500 km. These imagers are available in Red-Blue-Green (RGB), multispectral, and hyperspectral variants [48]. Other well-known COTS RGB, multispectral, and hyperspectral imaging solutions with considerable flight heritage for the visible and NIR spectrums include Dragonfly Aerospace's (Stellenbosch, South Africa) Gecko, Mantis, Chameleon, Caiman, and Komodo, high performance camera systems which can each offer a GSD of 39 m, 16 m, 10 m, 3.25 m, and 1.5 m, respectively, at the same altitude of 500 km [49]. Furthermore, Dragonfly Aerospace also offers a version of the Chameleon imager which is capable of operating in the SWIR spectrum, offering a resolution of four spectral bands between 1000 nm and 1750 nm wavelengths and providing an 8.7 m GSD and an 11.2 km swath from a \begin{table}
\begin{tabular}{c c} \hline \hline
**Band Definition** & **Band Wavelength Boundaries (\(\upmu\)m)** \\ \hline Visible & 0.38–0.75 \\ NIR & 0.75–1.4 \\ SWIR & 1.4–3 \\ MWIR * & 3–8 \\ LWIR * & 8–15 \\ FIR & 15–1000 \\ Microwave & 1000–1\(\times 10^{6}\) \\ \hline \hline \end{tabular}  
* The area covering MWIR and LWIR bands is also commonly referred to as the Thermal Infrared (TIR) band.  
\end{table} 
Table 3: A comparison among the wavelength boundaries of the distinct regions of the visible, Infrared (IR), and microwave bands of the electromagnetic spectrum. 500 km altitude [50]. Another example of an optical imaging sensor developed for CubeSat use is the SATLANTIS (Leioa-BILBAO, Spain) iSIM-90, a large high-resolution imaging instrument designed to be integrated with 12U and 16U CubeSat platforms. The iSIM90 is capable of operating in both visible, NIR, and SWIR spectral ranges simultaneously, providing a GSD of 2 m for visible and NIR wavelengths and a GSD of 5 m for SWIR from an altitude of 500 km [51]. Furthermore, Earth observation CubeSats can also be equipped with COTS IR spectrometers such as the Thothx (Deep River, ON, Canada) Argus 2000, which are capable of operating in the NIR and SWIR spectra, which can be utilized for Earth observation missions that include the study of atmospheric composition [52]. Apart from the use of COTS sensors, it is common for many Earth observation CubeSat missions to feature custom-made or in-house developed imagers and spectrometers as payload. A notable recent Earth observation CubeSat mission combining Visible and Near-Infrared (VNIR) multispectral imaging and NIR spectrometry is FACSAT-2, which involves the launch of a 6U CubeSat platform that was co-developed by the Colombian Air Force and GomSpace. FACSAT-2 was tasked with the mission of performing multispectral imaging duties over the Colombian territory as well as obtaining data regarding greenhouse gas (such as CO\({}_{2}\) and CH\({}_{4}\)) emissions. As its payload, FACSAT-2 was equipped with COTS optical instruments, namely the MultiScape100 (Simera Sense Europe BV, Leuven, Belgium) imager and the Argus 2000 (Thoth Technology Inc, Deep River, ON, Canada) spectrometer [53]. An example of a similar mission was the SATHYABAMASAT, a 2U CubeSat that was developed by Sathyabama University and ISRO under the mission of collecting data on the concentration and density of greenhouse gases such as water vapor and hydrogen fluoride CO\({}_{2}\) and CH\({}_{4}\), utilizing the Argus 1000 (Thoth Technology Inc, Deep River, ON, Canada) IR spectrometer as its mission-enabling payload [54; 55]. Another similar example is the OphiCraft-Zorkiy, a 6U Earth remote sensing spacecraft developed by the Russian company SPUTNIX LLC.