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The Story of a Comet Hunter's Life

My 50 years with Comets

Part 52: Comet Crommelin and Mr. Masamitsu Yamazaki, part 1

    In December 2016 a public lecture was held at Sagawa in Kochi prefecture to honor Mr. Masamitsu Yamazaki who had discovered Comet Crommelin. Comet Crommelin is a periodic comet with a 28-year orbital period. It was a comet of the Uranus family in the old nomenclature. As it was the first comet I was directly involved in, I have an unforgettable memory that will stay with me for the rest of my life. As a result, Mr. Yamazaki's name was given to the comet.
    Back in 1928, Mr. Masamitsu Yamazaki was working as an astronomy staff member at the then Mizusawa Latitude Observatory in Iwate prefecture. He discovered a comet using a strange-looking home-built telescope. His discovery was the first of the kind in Japan at that time and became big news. However, Dr. Andrew Crommelin of Royal Astronomical Society investigated it and came to a conclusion that it was an old comet which had appeared in 1818 and 1873. Consequently, Mr. Yamazki's name was not given to the comet. Instead, it was called Comet Crmmelin. It was expected to return in 1956.
    Mr. Yamazaki was born in Kochi prefecture. After retirement from the work at Mizusawa, he returned to his hometown Sagawacho and became a farmer. I went to see him to ask about the circumstances of his discovery in detail. At that time I was observing at home in Kochi. I was eagerly searching for a comet using a 15cm reflector. Mr. Yamazaki, too, was continuing to observe hoping for a reunion with the comet he had discovered 28 years earlier.
    Early in 1956, the orbital predictions of Mr. Yamazaki's comet was announced well in advance by the British Astronomical Association. However, we found a huge discrepancy between their predicted positions and our calculations jointly made with Mr. Yamazaki showing a difference of as much as 10 degrees . In the middle of autumn in October 1956, wondering whose predictions were correct, I was searching around Leo where the comet was predicted to appear. According to Mr. Yamazaki, the comet's orbit would be little perturbed by Jupiter and Saturn judging from its orbital path in relation to these planets. Furthermore, the calculations showed its orbital period was 28.0 years. This means the comet would appear in the same constellation where Mr. Yamazaki had discovered it.
    Was his prediction correct? At 4 o'clock on the morning of October 6, 1956, I spotted a suspicious glow in the sickle of the Lion, while searching the area. Was it the same comet that Mr. Yamazaki saw 28 years earlier? My heart was pounding with heightened expectations.


Mr. Yamazaki with his comet seeker



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