NACHOS: Nanosat Atmospheric Chemistry Hyperspectral Observation System
NACHOS, which consists of two 3U Cubesats (NACHOS-1 and NACHOS-2), will allow scientists to detect, map, and quantify Earth’s dilute trace gases more easily, which is critical for learning more about everything from volcanology to climate change. These CubeSat demonstrations will help researchers determine whether constellations of CubeSat-like small satellites could gather and process high-resolution imaging data as efficiently as larger, single-platform satellites – at a fraction of the cost. NACHOS-1 launched February 2022 and was subsequently deployed (~400km and 52deg inclination) from the departing Cygnus spacecraft on June 30, 2022. NACHOS-2 was launched directly into orbit (~500km and 44.9deg inclination) on July 2, 2022, onboard the Virgin Orbit LauncherOne.
Atmospheric trace gases seeping from Earth’s interior and pouring from human-made sources give scientists unique insights into the nuanced systems behind things like local weather patterns, the biosphere, and climate change. If successful, NACHOS will mark the a major shift in the way scientists approach measuring atmospheric trace gases using space-based remote sensors and allow researchers to study these gases with far greater ease.
Spaceborne trace gas spectral imaging requires both high spectral resolution and high sensitivity, generating very large volumes of data and traditionally entailing a large satellite platform. The NACHOS CubeSats feature an ultra-compact hyperspectral imager that pre-processes data in situ, targeting NO2, SO2, ozone, formaldehyde, and other gases with sufficient spectral resolution to confidently separate the trace gas signatures from the atmosphere. This would allow researchers to gather high-resolution data on atmospheric trace gases with small satellites, drastically reducing the overall mission cost and increasing revisit time and mission flexibility.
- An ultra-compact Offner-type hyperspectral imager will operate in the 290-500 nm spectral region, with f/2.9 optics, 1.3 nm resolution, 0.6 nm sampling, 350 contiguous spectral channels, and 350 across-track spatial pixels.
- A Teledyne/ e2v UV-optimized CCD array will have an integral full-frame readout buffer supporting high-frame readout rates. Internal LED-based onboard calibration provides CCD non-uniformity correction at 0.1%.
- Streamlined hyperspectral gas retrieval algorithms pre-processes data in situ, addressing the issue of limited telemetry bandwidth by reducing large data cubes down to a set of small 2D images and spectral sample sets.
Steven P. Love is an experimental physicist, spectroscopist, and remote sensing instrumentation scientist. He is the project’s principal investigator and optics lead. He received his PhD in physics from Cornell University in 1991, and he has been a technical staff member in the Space and Remote Sensing Group (ISR‐2) at the Department of Energy’s (DOE’s) Los Alamos National Laboratory (LANL) since 1994.
Steve is assisted by co-investigators Kirk Post, James Theiler, and Manvendra Dubey, and engineering team Magdalena Dale, Logan Ott, Claira Safi, Hannah Mohr, and Kerry Boyd, all of whom are currently at LANL.
S. P. Love, et al., “NACHOS, a CubeSat-based high-resolution UV-Visible hyperspectral imager for remote sensing of trace gases: System overview and science objectives,” Proc. SPIE 11832, CubeSats and SmallSats for Remote Sensing V, 118320E (2021). https://doi.org/10.1117/12.2594336
K. W. Post, et al., “The NACHOS CubeSat-based hyperspectral imager: Laboratory and field performance characterization,” Proc. SPIE 11832, CubeSats and SmallSats for Remote Sensing V, 118320F (2021). https://doi.org/10.1117/12.2594686
J. Theiler, B. R. Foy, C. L. Safi, and S. P. Love, “Onboard CubeSat data processing for hyperspectral detection of chemical plumes”, Proc. SPIE 10644, Algorithms and Technologies for Multispectral, Hyperspectral, and Ultraspectral Imagery XXIV, 1064405 (2018). https://doi.org/10.1117/12.2305278