Large impacts around a solar-analog star in the era of terrestrial planet formation

1Huan Y. A. Meng, 2Kate Y. L. Su, 1,2George H. Rieke, 3David J. Stevenson, 4,5Peter Plavchan, 2,6,7Wiphu Rujopakarn, 8Carey M. Lisse, 9Saran Poshyachinda, 10Daniel E. Reichart

1Lunar and Planetary Laboratory and Department of Planetary Sciences, University of Arizona, 1629 East University Boulevard, Tucson, AZ 85721, USA.
2Steward Observatory and Department of Astronomy, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721, USA.
3Division of Geological and Planetary Sciences, California Institute of Technology, MC 170-25, 1200 East California Boulevard, Pasadena, CA 91125, USA.
4NASA Exoplanet Science Institute, California Institute of Technology, MC 100-22, 770 South Wilson Avenue, Pasadena, CA 91125, USA.
5Missouri State University, 901 South National Avenue, Springfield, MO 65897, USA.
6Department of Physics, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330, Thailand.
7Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institute for Advanced Study, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, 277-8583, Japan.
8Space Department, Applied Physics Laboratory, Johns Hopkins University, 11100 Johns Hopkins Road, Laurel, MD 20723, USA.
9National Astronomical Research Institute of Thailand (Public Organization), Ministry of Science and Technology, 191 Siriphanich Building, Huay Kaew Road, Muang District, Chiang Mai 50200, Thailand.
10Department of Physics and Astronomy, Campus Box 3255, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.

The final assembly of terrestrial planets occurs via massive collisions, which can launch copious clouds of dust that are warmed by the star and glow in the infrared. We report the real-time detection of a debris-producing impact in the terrestrial planet zone around a 35-million-year-old solar-analog star. We observed a substantial brightening of the debris disk at a wavelength of 3 to 5 micrometers, followed by a decay over a year, with quasi-periodic modulations of the disk flux. The behavior is consistent with the occurrence of a violent impact that produced vapor out of which a thick cloud of silicate spherules condensed that were then ground into dust by collisions. These results demonstrate how the time domain can become a new dimension for the study of terrestrial planet formation.

Reference
Meng HYA, Su, KYL, Rieke GH, Stevenson DJ, Plavchan P, Rujopakarn W, Lisse CM, Poshyachinda S, Reichart DE (2014) Large impacts around a solar-analog star in the era of terrestrial planet Formation. Science 345, 6200, 1032-1035
Link to Article [DOI: 10.1126/science.1255153]

Reprinted with permission from AAAS

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