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The 1996-1997 Fading of V651 Mon, the Binary Central Star of the Planetary Nebula NGC 2346

Taichi Kato·Daisaku Nogami·Hajime Baba
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Abstract

V651 Mon is the binary central star of the bipolar planetary nebula NGC 2346. The star showed the second-ever deep fading in 1996-1997, which was presumably caused by obscuration by a dust cloud in the planetary nebula, as was proposed to explain the 1981-1985 event. The entire duration of the 1996-1997 event was \~400 d, remarkably shorter than the 1981-1985 event, suggesting that the obscuring body was smaller or had a larger tangential velocity. The most remarkable feature in this event was the presence of a sharply defined transient clearing (brightening). From the time-scale of the variation, we propose an upper limit of the projected scale of several times ~10^11 cm of the structure responsible for the brightening. This observation provides the first evidence for a sharply defined, small lucent structure within the obscuring body around the central star of NGC 2346

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Taichi Kato, Daisaku Nogami, Hajime Baba. 2001-12-13. The 1996-1997 Fading of V651 Mon, the Binary Central Star of the Planetary Nebula NGC 2346. https://doi.org/10.1093/pasj%2F53.5.901

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