Japan Geoscience Union Meeting 2015

Presentation information


Symbol P (Space and Planetary Sciences) » P-CG Complex & General

[P-CG30] New Progress toward the Understanding of Small Solar System Bodies

Tue. May 26, 2015 6:15 PM - 7:30 PM Convention Hall (2F)

Convener:*Masahiko Arakawa(Graduate School of Science, Kobe University), Taishi Nakamoto(Tokyo Institute of Technology), Sei-ichiro WATANABE(Division of Earth and Planetary Sciences, Graduate School of Science, Nagoya University), Masanao Abe(Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency), MASATERU ISHIGURO(Department of Physics and Astronomy, Seoul National University)

6:15 PM - 7:30 PM

[PCG30-P07] MU radar head echo observations of the 2012 October Draconid outburst

*Yasunori FUJIWARA1, Johan Kero2, Makoto ABO3, Csilla Szasz2, Takuji NAKAMURA4 (1.SOKENDAI, 2.Swedish Institute of Space Physics, 3.Tokyo Metropolitan University, 4.National Institute of Polar Research)

Keywords:meteor shower, radar observation, head echo

We present October Draconid meteor head echo observations with the Shigaraki middle and upper atmosphere (MU) radar in Japan. Prominent activity of 2012 October Draconids occurred between 16:20 UT and 17:40 UT on October 8. Around the peak time (13-20 h UT), the MU radar recorded 51 Draconid head echoes with precise orbit determinations. The weighted mean geocentric radiant during this time interval was α = 262.5 ± 0.5 in right ascension, δ = +55.8 ± 0.3 declination (degree, epoch J2000.0) with the weighted mean geocentric velocity of 20.6 ± 0.3 km s-1, which are in good agreement with model predictions. Although the models predicted no strong visually detectable activity, our head echo observations showed that the peak activity in 2012 was higher than that of the previous outburst in 2011. Based on the distribution of radar cross section (RCS) for the Draconid meteor head echo, the outburst in 2012 was due to meteoroids with lower masses (fainter meteors) than that in 2011.