Tomographic retrieval of thermosphere gravity waves from the Far Ultraviolet Imager (FUVI) on the future DYNAGLO CubeSat mission

Gravity waves (GWs) play a crucial role in the transfer of momentum and energy throughout the Earth's atmosphere; however, observations of these waves remain limited, particularly in the mesosphere and lower thermosphere (MLT) region. Tomographic methods offer a promising approach to leverage multiple line-of-sight measurements in order to resolve the 3D structures of atmospheric waves and provide valuable insights into behaviors such as wave propagation, interaction with background winds, and wave breaking phenomena.

The DYNamics Atmosphere GLObal-Connection (DYNAGLO) CubeSat mission will help fill a crucial observational gap in the thermosphere – gravity wave characterization. Planned to launch in late 2025, DYNAGLO will provide the community with global thermosphere gravity wave measurements and their characteristics to be correlated with known gravity wave sources (terrestrial and geomagnetic). DYNAGLO will use two 6U CubeSats in a string-of-pearls configuration, each with a miniaturized Far Ultraviolet Imager (FUVI) to provide common volume 2D nadir images (latitude, longitude) of neutral density variations at 150km. DYNAGLO science goals are to determine: (1) What spectrum of gravity waves are present in the thermosphere and to what extent are they driven by lower atmospheric sources of gravity waves? (2) Is there a spectrum of thermosphere gravity waves that are correlated with auroral activity?

Using FUVI in a nadir-pointing configuration, DYNAGLO will catalog the horizontal wavelengths of medium to large scale GWs (100 km to >1000 km), frequency of occurrence, geographic location, phase speeds (120 m/s to 1100 m/s), and direction of propagation over the dayside thermosphere including high latitude regions. By utilizing FUVI measurements for tomographic retrievals as well, DYNAGLO will be able to provide coincident observations of both vertical and horizontal wavelengths, which would enhance DYNAGLO science by providing a means to calculate other parameters, such as momentum flux, dissipation altitudes, and maximum wavelengths of propagating GWs prior to dissipation. In this presentation, we explore the application of tomographic methods using FUVI airglow measurements to resolve the vertical wavelengths of thermosphere gravity waves.