Heliophysics Science Division
Sciences and Exploration Directorate - NASA's Goddard Space Flight Center

February 23rd, 2018, 1:00 pm - 2:00 pm

August 24, 1:00 pm - 2:00 pm

A suite of sensors for observing the thermosphere



John Noto (CPI)

The Earth?s ionosphere is increasingly recognized as a region of space that has direct impact on the development and use of space assets for modern society. Monitoring the state of the ionosphere requires space-based instrumentation and preferably a fleet of spacecraft with identical instrumentation. Small CubeSats provide the capabilities to launch many identical platforms at reasonable total costs but they require miniaturized science instruments to fit within the limited size, weight, and power (SWAP) constraints. Presented here is a suite of optical sensors, operating in different wavelength regimes that can be used to monitor the composition, dynamics and variability of the ionosphere/thermosphere region from orbit and from the ground. These technologies are designed to complement and support Explorer-class atmospheric research, not supplant it. Ground-based measurements supplement those made by orbital assets by providing localized, time-resolved measurements of vital constituents of the ionosphere, such as total electron content (TEC), thermospheric neutral winds (TNW), airglow brightness and distribution (waves and disturbances), and composition. The first sensor a ?Doppler imager? which remotely measures winds and temperatures of the neutral background atmosphere at ionospheric altitudes of 87-300Km and possibly above. Incorporating both recent optical manufacturing developments, modern network awareness and the application of machine learning techniques for intelligent self-monitoring and data classification this system achieves cost savings in manufacturing, deployment and lifetime operating costs. Deployed in both ground and possibly space-based modalities, this cost-disruptive technology will allow computer models of, ionospheric variability and other space weather models to operate with higher precision. Other sensors can be folded into the data collection and analysis architecture easily creating autonomous virtual observatories. Ground-based variants of this sensor have recently been deployed in India and Brazil. This Doppler imager is capable of operation within the small volume and the challenging thermal environment of a CubeSat. The second sensor COMPASS, Compact Multi-Spectral Photometer for Space Science, is a narrowband VUV photometer with 20 times the sensitivity of larger multi-pixel spectrographs. COMPASS will complement Explorer mission VUV sensing through contemporaneous coverage of key atomic oxygen (130.4 and 135.6-nm) and molecular nitrogen Lyman-Birge-Hopfield (LBH) band emission features. The COMPASS development addresses the recommendation in the Decadal Survey for ?small space missions? to diversify space physics research by additionally enabling VUV research on CubeSat-scale vehicles. COMPASS enables global, multi-point, and trans-hemispheric constellation missions as a low-resource, flight-ready VUV photometer capable of supporting dayside, auroral zone, and nightside measurements at modest spatial resolution. Last but not least is the Nanosat Oxygen A-band Spatial Heterodyne Interferometer (NOASHIN). This Spatial Heterodyne Spectrometer, a variant of a Michelson interferometer has been developed to monitor the O2 A-band and measure rotational temperatures through the ratios of peak intensity. This robust technology is also adaptable to other emissions of interest.