The origin of the Ca(II) emission, in one of two plasma components, and the metallic abundances in a 2002 Leonid meteor spectrum Original Research Article

Fast-moving meteors such as Leonid meteors have two types of spectra. One is the main component composed of neutral atomic lines having low excitation temperature (∼5000 K) and the other is the hot component composed of singly ionized lines such as Mg(II) and Ca(II) having high excitation temperature (∼10,000 K). We observed the brightest fireball which appeared at, 03 h 47 m 54 s UT of November 19, 2002 in the 2002 Leonid aircraft campaign. The neutral atoms composing the main component such as Mg(I), Fe(I), Ca(I) and Na(I) were identified in the wavelength range of 300–650 nm. The singly ionized atomic emissions of Ca(II) and Mg(II) were also detected in this Leonid spectra during the temporal series of brightness of the fireball flight. So far, these emissions were considered to originate from the hot component. However, we found in several frames taken at the bright fireball during the period of the observation that the Ca(II) lines do not satisfy the hot-component condition even if the hot-component Mg(II) (448 nm) emission was observed. This indicates that the Ca(II) lines do not always satisfy the hot-component condition.