Intl symposium on space weather and habitable planets (27 and 28 June 2017)

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On 27-28 June, Kyoto University's Unit of Synergetic Studies for Space (USSS), Graduate School of Advanced Integrated Studies in Human Survivability (GSAIS, or "Shishu-Kan"), and Kwasan and Hida Observatories -- both belonging to the Graduate School of Science -- jointly hosted a "Symposium on Space Weather and Habitable Zones" in Higashi Ichijokan's Shishu-Kan Hall. The topics covered include the effects of solar and stellar flares on the evolution of planets and the emergence of life, and methods for predicting and evaluating these eruptions.

The program opened with a special lecture by Dr Vladimir S Airapetian from the Goddard Space Flight Center (GSFC) of the National Aeronautics and Space Administration's (NASA). The scientist has recently offered a possible explanation for the "faint young Sun paradox", suggesting that the Sun of some four billion years ago, while much fainter than it is today, frequently produced powerful flares, each sending a large amount of energetic particles to Earth. This influx of charged particles, he explained, may have contributed to the formation of nitrous oxide, a greenhouse gas, in the planet's atmosphere. This kept the ancient Earth warm enough to support life despite being under a faint Sun.

Dr Airapetian's presentation at the symposium explored "space weather-affected habitable zones" based on the latest observations and calculations, and introduced a new definition of habitable zones that factors in the effects of stellar winds. The lecture was followed by a wide-ranging Q&A session.

Professor Yosuke Yamashiki, of USSS and GSAIS, then presented an overview of ExoKyoto, an online database of extrasolar planets, and a new module for evaluating the effects of flares on these planets.

Professor Kazunari Shibata, director of the Kwasan and Hida Observatories and deputy director of USSS, reported on the latest research on coronal mass ejections (CMEs) associated with superflares, as well as their potential impacts on Earth. GSAIS Associate Professor Hiroaki Isobe discussed his efforts to analyze the solar superflares described in historical documents, while Graduate School of Science Assistant Professor Takanori Sasaki presented on an "aquaplanet formation simulator".

Other speakers included Dr Hiroyuki Maehara, a researcher at the National Astronomical Observatory of Japan (NAOJ), who explored the correlation between superflares and large starspots on sun-like stars. Three students from the Graduate School of Science -- Yuta Notsu, Kai Ikuta, and Kosuke Namekata -- each presented on a recent observational study on stellar flares. Associate Professor Daisaku Nogami, also of the Graduate School of Science, who shared his plans to study superflares using the University's new 3.8-meter telescope in Okayama Prefecture.

Kyoto University will continue to work with Dr Airapetian on an ongoing basis, most notably in observational research involving collaboration with NASA, and to improve ExoKyoto.

Dr Airapetian

Professor Yamashiki

Special lecture

Dr Airapetian (left) with former astronaut Takao Doi, program-specific professor at USSS

Symposium presenters and others

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