A bright member of the Phoenicid meteor shower appears at the bottom left of this photo taken at 02h15m39s UT on December 2, 2014. The Moon is captured to the lower right of center in the photo. Camera: Pentax K-3 + SIGMA 4.5mm F2.8, 3 second exposure time, at Sandy Point, North Carolina, U.S.A.. Credit: Hiroyuki Toda, NAOJ
The Phoenicid meteor shower (named after the constellation Phoenix) was discovered by the first Japanese Antarctic Research Expedition on December 5, 1956, during their voyage in the Indian Ocean. However, it has not been observed again. This has left astronomers with a mystery: where did the Phoenicids come from and where did they go?
Two Japanese teams have found an answer to these questions by linking the Phoenicid meteor shower to a vanished celestial body, Comet Blanpain. This comet appeared in 1819 for the first time and then disappeared. In 2003 astronomers discovered a minor body moving along the same orbit as Comet Blanpain had over 100 years ago and showed that it was the remains of Comet Blanpain. The iconic coma and tail of a comet are made of gas and dust which escaped from the surface of the nucleus. The reason why Comet Blanpain reappeared as an asteroid was probably because all the gas and dust have escaped from this central body. Now rather than calling the object a “comet” it might be more accurate to refer to it as an “asteroid.”
Although all of the gas and dust have escaped from Comet Blanpain into space, they now form a dust trail which revolves along almost the same orbit as Comet Blanpain itself, and gradually spread along the orbit. When such a dust trail encounters the Earth, the dust particles impinge into the atmosphere and ablate, which are observed as meteors.
Assuming that Comet Blanpain is the parent body of the Phoenicids, the teams performed calculations and predicted that the Phoenicids should be observed again on December 1, 2014. Following this prediction, the two teams of Japanese astronomers carried out a campaign of observation. One team led by Yasunori Fujiwara, a graduate student at the Department of Polar Science, SOKENDAI(The Graduate University for Advanced Studies), and Takuji Nakamura, a professor of the National Institute of Polar Research/SOKENDAI, traveled to North Carolina, U.S.A., and observed there. The other team led by Mikiya Sato, an astronomical officer at Kawasaki Municipal Science Museum, and Junichi Watanabe, a professor of the National Astronomical Observatory of Japan/SOKENDAI, visited La Palma Island in the Spanish territory off the West coast of Africa for observations. The weather condition at the former site was comparatively good, but more clouds covered at the latter site. Therefore, Sato’s team supplementary used data from other sources such as NASA’s All Sky Fireball Network and radar observations at the University of Western Ontario, Canada.
https://www.soken.ac.jp/en/en-news/38848/
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