Global-scale observations and modeling of far-ultraviolet airglow during twilight

The NASA Global-scale Observations of the Limb and Disk ultraviolet imaging spectrograph performs observations of upper atmosphere airglow from the sunlit disk and limb of the Earth, in order to infer quantities such as the composition and temperature of the thermosphere. To interpret the measurements, the observational and solar illumination geometry must be considered. We use forward models of upper atmosphere density and composition, photoelectron impact, airglow emissions, radiative transfer, and line-of-sight integration, to describe the expected observations, and here test those calculations against observations near the terminator, and near the limb. On the nightside of the terminator, broad regions of faint airglow are seen, particularly near the winter solstice. These are caused by photoelectrons generated in magnetically conjugate areas in the other hemisphere that are still illuminated, transported along field lines, and then precipitated back into the atmosphere. Model calculations demonstrate that this process is the source of the emission, and obtain good agreement with its morphology and intensity. In some regions, the observed emissions are not as bright as the model simulations. Some of the reduction in electron flux is explained by changes in magnetic field strength; in other cases, particularly at high magnetic latitude, the cause is unknown, but must occur along extended field lines that reach into the plasma sheet.

To Access Resource:

Questions? Email Resource Support Contact:

  • opensky@ucar.edu
    UCAR/NCAR - Library

Resource Type publication
Temporal Range Begin N/A
Temporal Range End N/A
Temporal Resolution N/A
Bounding Box North Lat N/A
Bounding Box South Lat N/A
Bounding Box West Long N/A
Bounding Box East Long N/A
Spatial Representation N/A
Spatial Resolution N/A
Related Links N/A
Additional Information N/A
Resource Format PDF
Standardized Resource Format PDF
Asset Size N/A
Legal Constraints

Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.


Access Constraints None
Software Implementation Language N/A

Resource Support Name N/A
Resource Support Email opensky@ucar.edu
Resource Support Organization UCAR/NCAR - Library
Distributor N/A
Metadata Contact Name N/A
Metadata Contact Email opensky@ucar.edu
Metadata Contact Organization UCAR/NCAR - Library

Author Solomon, Stanley C.
Andersson, L.
Burns, Alan
Eastes, R. W.
Martinis, C.
McClintock, W. E.
Richmond, Arthur D.
Publisher UCAR/NCAR - Library
Publication Date 2020-03-01T00:00:00
Digital Object Identifier (DOI) Not Assigned
Alternate Identifier N/A
Resource Version N/A
Topic Category geoscientificInformation
Progress N/A
Metadata Date 2025-07-11T19:21:15.726249
Metadata Record Identifier edu.ucar.opensky::articles:23269
Metadata Language eng; USA
Suggested Citation Solomon, Stanley C., Andersson, L., Burns, Alan, Eastes, R. W., Martinis, C., McClintock, W. E., Richmond, Arthur D.. (2020). Global-scale observations and modeling of far-ultraviolet airglow during twilight. UCAR/NCAR - Library. https://n2t.org/ark:/85065/d7m90cvk. Accessed 01 August 2025.

Harvest Source