The 2007 Aurigid meteor outburst

Abstract

A rare outburst of the Aurigid meteor shower was predicted to occur on 2007 September 1 at 11:36 ± 20 min ut due to Earth's encounter with the one‐revolution dust trail of long‐period comet C/1911 N1 (Kiess). The outburst was predicted to last ∼1.5 h with peak zenithal hourly rate of ∼200 h−1, which is ∼20 times higher than the annual Aurigid shower. Three members of Armagh Observatory observed this outburst from the general area of San Francisco, CA, USA, where the shower was anticipated to be best seen. Observed radiant, velocity and activity peak time were consistent with the predictions, whereas the zenithal hourly rate was about half of the predicted value. Five Aurigids were observed by two stations simultaneously, enabling their spatial trajectory to be worked out. The orbits of these double station meteors are in good agreement with that of their parent comet Kiess. The outburst was abundant in bright (−2 to +1 mag) meteors. The first high‐altitude Aurigid, with a beginning height of 137.1 km, was recorded.

September epsilon Perseids observed by the Czech Fireball Network

“…The orbital period of the comet Thatcher is about 415 yr and the semi-major axis of the mean photographic orbit of nine Lyrid fireballs is 67 AU, which is an orbital period of 540 yr (Gajdoš & Porubčan 2005). The orbital period of the comet Kiess is about 2000 yr and recently, an outburst of Aurigids was observed in 2007 (Rendtel 2007;Jenniskens & Vaubaillon 2008;Atreya & Christou 2009). Unfortunately, only five double-station video meteors are available and the accuracy of velocity measurements is not sufficient so it was difficult to compute the semi-major axis accurately.…”