Meteor luminosity at 160 km altitude from TV observations for bright Leonid meteors

Two atmospheric trajectories have been determined by simultaneous observations with image intensifier-fitted TV cameras and conventional photographic cameras for two bright Leonid meteors (fireballs) in 1995 and 1996. Beginning heights recorded by the photographic method are lower than about 130 km, but those observed by the TV systems are closer to 160 km. The primary reason for this difference is the sensitivity of the observing systems. However, the difference in the sensitive wavelengths (up to 900 nm for the TV systems) could be another factor contributing to the large difference between the two methods. This suggests that the beginning heights of high speed bright meteors such as Leonid meteors are much higher than previously thought.