A luminous and extremely tenuous region at the outer limit of the exosphere, consisting chiefly of ionized hydrogen and extending to approx. fifteen earth radii; also called protonosphere.
Origin
1950s.
Definition of geocorona in US English:
geocorona
nounˌdʒiːə(ʊ)kəˈrəʊnə
Atmospheric Physics
A luminous and extremely tenuous region at the outer limit of the exosphere, consisting chiefly of ionized hydrogen and extending to approx. fifteen earth radii; also called protonosphere.