Figure 1: Optical spectrum of the 05:15:16 UT Leonid.
NEW MOLECULAR BAND DETECTED
The SETI Institute cooled CCD spectrograph (P. Jenniskens, P.I.)
was very successful in capturing
optical spectra of Leonid meteors during the 2002 Leonid MAC mission.
The instrument was operated by
Emily Schaller
of Caltech, who captured the particularly nice result shown above.
This meteor shows a newly discovered molecular band emission
in an early part of its trajectory, idenfied as the molecular oxygen B-band,
where the metal atom ablation lines are still weak.
Figure 2: Leonid meteor and afterglow
SPECTRA OF FAINT METEORS
Faint meteors were targeted by the NASA Ames code JIT videographers
Greg Merkes and Jesse Carpenter onboard FISTA, who filmed hundreds of spectra of
intrinsically faint meteors with a High Definition TV camera and
the SETI Institute low-resolution spectrograph. Sometimes,
a bright meteor is also captured. The figure above shows
afterglow and recombination lines, discovered in prior campaigns
by Jiri Borovicka and
Peter Jenniskens.
Figure 3: Optical spectrum of the -1 magnitude 04:24:20 UT Leonid, observed
visually through the aircraft window.
HUNDREDS OF LOW RESOLUTION SPECTRA RECORDED
Jiri Borovicka reports that the Ondrejov video spectrometer worked well.
At least 130 low resolution meteor spectra of various
quality were obtained during the first 90 minutes of observation,
which included the 4 UT peak. A summary image of one of the best
spectra is shown. This completes homogeneous material of Leonid
video spectra taken with the same camera in 5 different years (1998-2002).
These data will be used to compare meteors from various trails, mainly in
respect of the Na/Mg/Fe ratios and of the effect of early release of sodium.
