geocoronium

== English == === Etymology === From geo- +‎ corona +‎ -ium, coined by Alfred Wegener in 1911. === Noun === geocoronium (uncountable) (geophysics, meteorology, obsolete) A hypothetical gaseous chemical element proposed to explain certain spectroscopic lines, and the green glow, found in the polar aurorae, that was later found to be explained by singly-ionized oxygen. ==== Coordinate terms ==== coronium nebulium ==== Related terms ==== coronium geocorona corona ==== See also ==== aurora