Ionospheric dynamo theory for production of far ultraviolet emissions on Uranus

Details Ionospheric dynamo theory for production of far ultraviolet emissions on Uranus Ionospheric dynamo theory for production of far ultraviolet emissions on Uranus

Jun 1989

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1989jgr....94.6517h&link_type=abstract

Journal of Geophysical Research (ISSN 0148-0227), vol. 94, June 1, 1989, p. 6517-6522.

Physics

18

Dynamo Theory, Planetary Ionospheres, Ultraviolet Radiation, Uranus Atmosphere, Elastic Scattering, Electron Acceleration, Field Aligned Currents, Ionization Cross Sections, Photoelectrons, Scattering Cross Sections, Uranus, Ionosphere, Dynamo, Ultraviolet, Wavelengths, Emissions, Origin, Formation, Electroglow, Lyman-Alpha Radiation, Acceleration, Giant Planets, Electrons, Diagrams, Currents, Electrical Properties, Magnetic Fields, Calculations, Homopause, Models, Electrical Fields

Scientific paper

A model is presented to explain diffuse FUV emissions from the outer planets, specifically Uranus, in excess of those diffuse emissions that are currently explainable by scattering of sunlight and/or excitation by photoelectrons. These electroglow emissions in H Ly-alpha and H2 bands, which occur in the sunlit hemisphere slightly above the homopause, appear to require particle excitation in the 10- to 50-eV range. An in situ mechanism for accelerating photoelectrons (and ions is proposed, involving neutral wind dynamo generation of field-aligned currents analogous to what occurs in the earth's equatorial E and F regions. Sufficiently strong field-aligned currents are found in the model calculation for Uranus to produce a potential drop of about 100 eV or greater between the F peak and homopause, concentrated at lower altitudes, and capable in principle of accelerating photoelectrons (and ions) to the 10- to 50-eV energies required to explain the observed emissions. The fact that the excitation and ionization cross sections are larger than elastic scattering cross sections in an H2 atmosphere at these energies makes in situ acceleration feasible for the production of UV on the outer planets.

Affiliated with

Also associated with

No associations

Rating

Ionospheric dynamo theory for production of far ultraviolet emissions on Uranus does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Ionospheric dynamo theory for production of far ultraviolet emissions on Uranus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ionospheric dynamo theory for production of far ultraviolet emissions on Uranus will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1855429