Articles | Volume 40, issue 3
https://doi.org/10.5194/angeo-40-271-2022
https://doi.org/10.5194/angeo-40-271-2022
Regular paper
 | 
06 May 2022
Regular paper |  | 06 May 2022

Terrestrial exospheric dayside H-density profile at 3–15 RE from UVIS/HDAC and TWINS Lyman-α data combined

Jochen H. Zoennchen, Hyunju K. Connor, Jaewoong Jung, Uwe Nass, and Hans J. Fahr

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Cited articles

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Bailey, J. and Gruntman, M.: Observations of exosphere variations during geomagnetic storms, Geophys. Res. Lett., 40, 1907–1911, https://doi.org/10.1002/grl.50443, 2013. 
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Bishop, J.: Geocoronal structure: The effect of solar radiation pressure and plasmasphere interaction, J. Geophys. Res., 90, 5235–5245, 1985. 
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Short summary
Exospheric Ly-α observations of UVIS/HDAC at CASSINI on its Earth swing-by and TWINS are combined to derive the exospheric H-density profile of the ecliptic dayside between 3–15 RE. At 10 RE nH=35 cm−3 is found in the vicinity of the subsolar point for quiet space weather conditions. Also a faster radial fall of the dayside H density above 8 RE (r−3) compared to lower distances of 3–7 RE (r−2.37) is found and possibly indicates enhanced loss of H atoms near the magnetopause and beyond.