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arXiv · 2206.06693

ET White Paper: To Find the First Earth 2.0

Jian Ge·Hui Zhang·Weicheng Zang·Hongping Deng·Shude Mao·Ji-Wei Xie·Hui-Gen Liu·Ji-Lin Zhou·Kevin Willis·Chelsea Huang·Steve B. Howell·Fabo Feng·Jiapeng Zhu·Xinyu Yao·Beibei Liu·Masataka Aizawa·Wei Zhu·Ya-Ping Li·Bo Ma·Quanzhi Ye·Jie Yu·Maosheng Xiang·Cong Yu·Shangfei Liu·Ming Yang·Mu-Tian Wang·Xian Shi·Tong Fang·Weikai Zong·Jinzhong Liu·Yu Zhang·Liyun Zhang·Kareem El-Badry·Rongfeng Shen·Pak-Hin Thomas Tam·Zhecheng Hu·Yanlv Yang·Yuan-Chuan Zou·Jia-Li Wu·Wei-Hua Lei·Jun-Jie Wei·Xue-Feng Wu·Tian-Rui Sun·Fa-Yin Wang·Bin-Bin Zhang·Dong Xu·Yuan-Pei Yang·Wen-Xiong Li·Dan-Feng Xiang·Xiaofeng Wang·Tinggui Wang·Bing Zhang·Peng Jia·Haibo Yuan·Jinghua Zhang·Sharon Xuesong Wang·Tianjun Gan·Wei Wang·Yinan Zhao·Yujuan Liu·Chuanxin Wei·Yanwu Kang·Baoyu Yang·Chao Qi·Xiaohua Liu·Quan Zhang·Yuji Zhu·Dan Zhou·Congcong Zhang·Yong Yu·Yongshuai Zhang·Yan Li·Zhenghong Tang·Chaoyan Wang·Fengtao Wang·Wei Li·Pengfei Cheng·Chao Shen·Baopeng Li·Yue Pan·Sen Yang·Wei Gao·Zongxi Song·Jian Wang·Hongfei Zhang·Cheng Chen·Hui Wang·Jun Zhang·Zhiyue Wang·Feng Zeng·Zhenhao Zheng·Jie Zhu·Yingfan Guo·Yihao Zhang·Yudong Li·Lin Wen·Jie Feng·Wen Chen·Kun Chen·Xingbo Han
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Abstract

We propose to develop a wide-field and ultra-high-precision photometric survey mission, temporarily named "Earth 2.0 (ET)". This mission is designed to measure, for the first time, the occurrence rate and the orbital distributions of Earth-sized planets. ET consists of seven 30cm telescopes, to be launched to the Earth-Sun's L2 point. Six of these are transit telescopes with a field of view of 500 square degrees. Staring in the direction that encompasses the original Kepler field for four continuous years, this monitoring will return tens of thousands of transiting planets, including the elusive Earth twins orbiting solar-type stars. The seventh telescope is a 30cm microlensing telescope that will monitor an area of 4 square degrees toward the galactic bulge. This, combined with simultaneous ground-based KMTNet observations, will measure masses for hundreds of long-period and free-floating planets. Together, the transit and the microlensing telescopes will revolutionize our understandings of terrestrial planets across a large swath of orbital distances and free space. In addition, the survey data will also facilitate studies in the fields of asteroseismology, Galactic archeology, time-domain sciences, and black holes in binaries.

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Jian Ge, Hui Zhang, Weicheng Zang, Hongping Deng, Shude Mao, Ji-Wei Xie, Hui-Gen Liu, Ji-Lin Zhou, Kevin Willis, Chelsea Huang, Steve B. Howell, Fabo Feng, Jiapeng Zhu, Xinyu Yao, Beibei Liu, Masataka Aizawa, Wei Zhu, Ya-Ping Li, Bo Ma, Quanzhi Ye, Jie Yu, Maosheng Xiang, Cong Yu, Shangfei Liu, Ming Yang, Mu-Tian Wang, Xian Shi, Tong Fang, Weikai Zong, Jinzhong Liu, Yu Zhang, Liyun Zhang, Kareem El-Badry, Rongfeng Shen, Pak-Hin Thomas Tam, Zhecheng Hu, Yanlv Yang, Yuan-Chuan Zou, Jia-Li Wu, Wei-Hua Lei, Jun-Jie Wei, Xue-Feng Wu, Tian-Rui Sun, Fa-Yin Wang, Bin-Bin Zhang, Dong Xu, Yuan-Pei Yang, Wen-Xiong Li, Dan-Feng Xiang, Xiaofeng Wang, Tinggui Wang, Bing Zhang, Peng Jia, Haibo Yuan, Jinghua Zhang, Sharon Xuesong Wang, Tianjun Gan, Wei Wang, Yinan Zhao, Yujuan Liu, Chuanxin Wei, Yanwu Kang, Baoyu Yang, Chao Qi, Xiaohua Liu, Quan Zhang, Yuji Zhu, Dan Zhou, Congcong Zhang, Yong Yu, Yongshuai Zhang, Yan Li, Zhenghong Tang, Chaoyan Wang, Fengtao Wang, Wei Li, Pengfei Cheng, Chao Shen, Baopeng Li, Yue Pan, Sen Yang, Wei Gao, Zongxi Song, Jian Wang, Hongfei Zhang, Cheng Chen, Hui Wang, Jun Zhang, Zhiyue Wang, Feng Zeng, Zhenhao Zheng, Jie Zhu, Yingfan Guo, Yihao Zhang, Yudong Li, Lin Wen, Jie Feng, Wen Chen, Kun Chen, Xingbo Han. 2022-06-14. ET White Paper: To Find the First Earth 2.0. https://arxiv.org/abs/2206.06693

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