# An Overview of CubeSat Missions and Applications
## 3 CubeSats as Earth Observation and Earth Science Platforms
### The Role of CubeSats in Earth Observation Missions
For its mission, OphiCraft-Zorkiy was equipped with a high-resolution imaging sensor capable of acquiring image data with a resolution of up to 6.6 m per pixel from LEO while the satellite was also equipped with two wide-angle cameras that were utilized for the purpose of visual observation and control of spacecraft's systems. The primary goal of the mission revolved around the in-orbit demonstration and validation of the satellite's primary imaging payload, as well as for a variety of its bus subsystems and a newly developed launch canister [56; 57]. Notable examples of more capable Earth observation CubeSat platforms also developed by SPUTNIX LLC are the Zorkiy-2M series of 12U CubeSats. Each of the Zorkiy-2M CubeSats is equipped with an optical instrument capable of acquiring images with a resolution of approximately 2.75 m per pixel and a maximum swath of 14 km from orbital altitudes between 500 km and 600 km, which can operate at four spectral ranges, namely, red, green, blue, and NIR. Furthermore, along with their primary Earth observation payload, the Zorkiy-2M satellites are also equipped with an Automatic Identification System (AIS) which is used to provide naval vessels with safety-of-navigation services along the Northern Sea routes [58; 59]. Another example of a recent optical-imaging Earth observation CubeSat mission is HORACIO, a 16U satellite manufactured by NanoAvionics which is equipped with the SATLANTIS (Leioa-BILBAO, Spain) iSIM-90 high resolution imager as its main payload, under the mission of acquiring Earth observation data that will be utilized for applications including coastal monitoring, border security, methane emissions quantification, infrastructure monitoring, and agriculture. HORACIO's imaging payload enables simultaneous image acquisition in visible, NIR, as well as SWIR spectral ranges, with four bands dedicated towards the visible spectrum and six towards NIR and SWIR spectra. The satellite was placed in a Sun-synchronous orbit with an altitude between 520 km and 590 km. From there, it is expected to provide images with the best possible resolution of 2 m and a swath of 14 km [60]. One more example of a contemporary Earth observation mission involving CubeSat platforms in the imaging role is the case of the Advanced Nanosatellites Systems for Earth Observation Research (ANSER) which is overseen by the Spanish Institute of Aerospace Technology (INTA). This constellation comprises three 3U CubeSats which are equipped with Complementary Metal Oxide Semiconductor (CMOS) imaging photometers and are connected via inter-satellite communication links. These CubeSats fly in formation using fuel-free, aerodynamic orbital maneuvering techniques and are utilized for monitoring the water quality in reservoirs and swamps in the regions of Spain and Portugal by identifying the presence of chemical pollutants and microorganisms such as phytoplankton or algal blooms within the water [61; 62; 63]. Another example of an ongoing Earth observation CubeSat mission is the Repeater Arrangement & Disaster Early View (RANDEV) 3U CubeSat, which is developed and operated by the Aerospace Systems and Control Laboratory of the Korea Advanced Institute of Science and Technology. This CubeSat is capable of capturing images with wavelengths between 350 nm and 900 nm (VNIR spectrum), supporting 58 individual spectral bands. The main mission of RANDEV is the observation of volcanoes, coastal areas, and cloud cover, and the extraction of data that would be used to identify potential hazards [64]. An example of a similar mission was the Forest Observation and Recognition Experimental Smallsat Thermal Detector-1 (FOREST-1), a 6U CubeSat created by the collaborative efforts of Spire Global, Inc. and OroraTech GmbH (Munich, Germany) which was equipped with the SAFIRE Gen-1 (OroraTech GmbH, Munich, Germany), a TIR sensory instrument capable of operating in both MWIR and LWIR spectral bands, providing a GSD of 250 m and a swath of 160 km. The SAFIRE Gen-1 sensor also incorporates an RGB camera.