PF191012 Myszyniec – highest Orionid meteor ever recorded

Abstract

On the night of Oct. 18/19, 2012, at 00:23 UT, a −14.7 mag Orionid fireball occurred over northeastern Poland. The precise orbit and atmospheric trajectory of the event are presented, based on the data collected by five video stations and one photographic Polish Fireball Network station. The beginning height of the meteor is 168.4 ± 0.6 km, which makes the PF191012 Myszyniec fireball the highest ever observed, well-documented meteor not belonging to the Leonid shower. The ablation became the dominant source of light of the meteor at a height of around 115 km. The thermalization of sputtered particles is suggested to be the source of radiation above that value. The transition height of 115 km is 10−15 km below the transition heights derived for Leonids and might suggest that the material of Leonids is more fragile and probably has smaller bulk density than that of Orionids.

Bright Perseid fireball with exceptional beginning height of 170 km observed by different techniques

“…Based on the comparison to the spectrum (see below), the first height (125 km) is connected with the start of ablation of volatile part (Na) and the second height with the start of intensive evaporation. When we compare the altitude of EN120812, where the ablation starts to be dominant (according to the light curve), with other meteors we can sort meteor showers as follows: 125 km for 71 km s −1 Leonids (Spurný et al 2000a,b;Koten et al 2006), 115 km for 68 km s −1 Orionid (Olech et al 2013), and 125 km for 60 km s −1 EN120812 Perseid. The orbit of EN120812 is one of the most precise photographic orbits ever determined for a Perseid fireball.…”

“…High-altitude meteors (beginning heights above 130 km) were observed predominantly in the Leonid meteor stream (meteor velocity 71 km s −1 ) (Fujiwara et al 1998;Spurný et al 2000a,b;Koten et al 2006), but also among η-Aquariids (67 km s −1 ), Perseids (60 km s −1 ), Lyrids (45 km s −1 ) (Koten et al 2001), and Orionids (68 km s −1 ) (Olech et al 2013). Here we report a Perseid fireball with a higher beginning than any of these meteors except Leonids.…”