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The 2022 Tongan volcanic eruption released significant energy into the atmosphere. Tropospheric satellite images show that the eruption generated pressure waves that traveled globally. The Global Observation of the Limb and Disk (GOLD) mission observed significant wave‐like thermospheric temperature perturbations (>100 K) from 12 to 16 UT. These temperature perturbations' spatial curvatures and arrival times are initially similar to the tropospheric wave‐fronts but differ significantly with eastward propagation. The perturbations had a phase speed of ∼300–400 m/s and wavelengths greater than 2,400 km. Near‐concurrent Ionospheric Connection Explorer neutral wind measurements suggest that the eruption's effects reversed the direction of the prevailing thermospheric zonal winds around the perturbed regions. The eruption's global and whole atmospheric effects provide a unique opportunity to study how different atmospheric layers exchange energy and momentum during explosive events. GOLD's synoptic observations are uniquely positioned to study these effects in the middle thermosphere.

Current and previous thermospheric remote sensing missions use N₂Lyman‐Birge‐Hopfield (LBH) band dayglow emission measurements to retrieve line‐of‐sight thermospheric composition and temperature. The precision of thermospheric composition and temperature retrieved from observations depends on the uncertainty in the relative LBH vibrational populations. In the laboratory, electron impact induced LBH emission measurements have shown that the relative vibrational populations change with gas pressure. However, it is not fully understood how these populations change for dayglow observations where the emissions that contribute to the observations vary with solar illumination and line‐of‐sight geometry. We quantify the relative vibrational populations as a function of solar zenith angle (SZA) and tangent altitude using Global‐scale Observations of Limb and Disk mission's LBH dayglow observations. We find that, while some lower vibrational levels show potential enhancement with increasing pressure (decreasing altitude), in general, they do not change significantly with SZA or tangent altitude for dayglow observations. The vibrational populations can thus be assumed as fixed parameters when retrieving neutral disk temperatures from remotely sensed LBH dayglow observations.

We have measured the 30 and 100 eV far ultraviolet (FUV) emission cross sections of the optically allowed Fourth Positive Group (4PG) band system (A¹Π → X¹Σ⁺) of CO and the optically forbidden O (⁵S^o → ³P) 135.6 nm atomic transition by electron‐impact‐induced‐fluorescence of CO and CO₂. We present a model excitation cross section from threshold to high energy for theA¹Π state, including cascade by electron impact on CO. TheA¹Π state is perturbed by triplet states leading to an extended FUV glow from electron excitation of CO. We derive a model FUV spectrum of the 4PG band system from dissociative excitation of CO₂, an important process observed on Mars and Venus. Our unique experimental setup consists of a large vacuum chamber housing an electron gun system and the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission Imaging Ultraviolet Spectrograph optical engineering unit, operating in the FUV (110–170 nm). The determination of the total Oi(⁵S^o) at 135.6 nm emission cross section is accomplished by measuring the cylindrical glow pattern of the metastable emission from electron impact by imaging the glow intensity about the electron beam from nominally zero to ~400 mm distance from the electron beam. The study of the glow pattern of Oi(135.6 nm) from dissociative excitation of CO and CO₂indicates that the Oi(⁵S^o) state has a kinetic energy of ~1 eV by modeling the radial glow pattern with the published lifetime of 180 μs for the Oi(⁵S^o) state.