This paper presents findings from a spaceborne Earth observation experiment using a novel, ultra-compact hyperspectral imaging camera aboard a 3U CubeSat. The camera employs an Offner optical scheme to capture hyperspectral images of terrestrial regions with a 200 m spatial resolution and 12 nm spectral resolution across a 400–1000 nm wavelength range, covering 150 channels in the visible and near-infrared spectrums. The hyperspectrometer is designed for deployment on a 3U CubeSat, featuring a robust all-metal cylindrical body and a coaxial arrangement of optical elements for optimal compactness and vibration stability. Performance was evaluated through numerical simulations, and analysis of hyperspectral data from a year-long orbital operation demonstrated the 3U CubeSat's ability to produce vegetation indices, including the normalized difference vegetation index (NDVI). A comparative study with Sentinel-2 L2A data showed strong agreement, confirming the 3U CubeSat's suitability for hyperspectral imaging in the visible and near-infrared spectrums. The ISOI 3U CubeSat can generate unique index images beyond Sentinel-2 L2A, highlighting its potential for advancing remote sensing applications. The design includes a compact, commercially available lens and a diffraction grating-based optical system, with a radially-mounted configuration to mitigate thermal deformation effects. The hyperspectrometer's performance was validated through simulations and real-world data, showing high spectral resolution and resolution matching design specifications. The satellite's capabilities in the visible to near-infrared spectrum offer higher spectral channel density compared to Sentinel-2 L2A, enabling detailed vegetation analysis. Future plans include transitioning to a 6U satellite platform for improved resolution and additional features.This paper presents findings from a spaceborne Earth observation experiment using a novel, ultra-compact hyperspectral imaging camera aboard a 3U CubeSat. The camera employs an Offner optical scheme to capture hyperspectral images of terrestrial regions with a 200 m spatial resolution and 12 nm spectral resolution across a 400–1000 nm wavelength range, covering 150 channels in the visible and near-infrared spectrums. The hyperspectrometer is designed for deployment on a 3U CubeSat, featuring a robust all-metal cylindrical body and a coaxial arrangement of optical elements for optimal compactness and vibration stability. Performance was evaluated through numerical simulations, and analysis of hyperspectral data from a year-long orbital operation demonstrated the 3U CubeSat's ability to produce vegetation indices, including the normalized difference vegetation index (NDVI). A comparative study with Sentinel-2 L2A data showed strong agreement, confirming the 3U CubeSat's suitability for hyperspectral imaging in the visible and near-infrared spectrums. The ISOI 3U CubeSat can generate unique index images beyond Sentinel-2 L2A, highlighting its potential for advancing remote sensing applications. The design includes a compact, commercially available lens and a diffraction grating-based optical system, with a radially-mounted configuration to mitigate thermal deformation effects. The hyperspectrometer's performance was validated through simulations and real-world data, showing high spectral resolution and resolution matching design specifications. The satellite's capabilities in the visible to near-infrared spectrum offer higher spectral channel density compared to Sentinel-2 L2A, enabling detailed vegetation analysis. Future plans include transitioning to a 6U satellite platform for improved resolution and additional features.