An ultraviolet-visible spectrum between 300 and 450 nm of a cometary meteoroid that originated from 55P/Tempel-Tuttle was investigated , and its new molecules , induced by atmospheric interaction , were discovered .
The spectroscopy was carried out using an intensified high-definition TV camera with a slitless reflection grating during the 2001 Leonid meteor shower over Japan .
A best-fit calculation mixed with atoms and molecules confirmed the first discovery of N _ { 2 } ^ { + } ~ { } B ^ { 2 } \Sigma _ { u } ^ { + } \rightarrow X ^ { 2 } \Sigma _ { g } ^ { + } bands in the UV meteor spectrum .
The N _ { 2 } ^ { + } temperature was estimated to be 10,000 K with a low number density of 1.55 \times 10 ^ { 5 } cm ^ { -3 } .
Such unexpectedly strong ultraviolet emission , in particular for N _ { 2 } ^ { + } ( 1,0 ) at 353.4 nm , is supposed to be formed through the wide dimensions of high-temperature regions caused by a large meteoroid .
Spectroscopic observations of reentry capsules will provide us with good opportunities for confirming the discovered N _ { 2 } ^ { + } .