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Abstract The geomagnetic storm on February 3, 2022 caused the loss of 38 Starlink satellites of Space‐X. The Global‐scale Observations of the Limb and Disk (GOLD) observations and Multi‐Scale Atmosphere Geospace Environment (MAGE) model simulations are utilized to investigate the thermospheric composition responses to the Space‐X storm. The percentage difference of the GOLD observed thermospheric O and N2column density ratio (∑O/N2) between the storm time (February 3, Day‐of‐Year [DOY] 34) and quiet time (DOY 32) shows a depletion region in the local noon sector mid‐high latitudes in the southern hemisphere, which corresponds to the east side of GOLD field‐of‐view (FOV). This is different from the classic theory of thermospheric composition disturbance during geomagnetic storms, under which the ∑O/N2depletion is usually generated at local midnight and high latitudes, and thus, appear on the west side of GOLD FOV. MAGE simulations reproduce the observations qualitatively and indicate that the ∑O/N2depletion is formed due to strong upwelling in the local morning caused by strong Joule heating. Interestingly, enhanced equatorward winds appear near local midnight, but also in the local morning sector, which transports ∑O/N2depletion equatorward. The depletion corotates toward the local afternoon and is observed in the GOLD FOV. The equatorward winds in the local morning are due to the ion‐neutral coupling under the conditions of a dominant positive interplanetary magnetic field east‐west component (By) during the storm.
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Thermospheric wind and temperature observations from El Leoncito Observatory in southern South America
A Fabry–Perot interferometer (FPI) installed at El Leoncito Observatory, Argentina (31.8oS, 69.3oW, 18omag lat), provides data on neutral winds and temperature over southern South America, a region lacking ground-based thermospheric observations. We present the climatology of neutral winds obtained from 630.0 nm airglow emissions. Results are shown for different seasons and different levels of solar activity. Temperature results are shown only for medium-to-high solar activity conditions. The modeled neutral winds show better agreement during high solar activity conditions. The modeled temperatures underestimate the observed values and do not reproduce the midnight temperature maximum observations. These observations will help improve model predictions of thermospheric parameters for this region.
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- PAR ID:
- 10660197
- Publisher / Repository:
- Frontiers Media SA
- Date Published:
- Journal Name:
- Frontiers in Astronomy and Space Sciences
- Volume:
- 12
- ISSN:
- 2296-987X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.3389/fspas.2025.1666096
