The NASA-UC Eta-Earth Program: I. A Super-Earth Orbiting HD 7924
Andrew W. Howard, John A. Johnson, Geoffrey W. Marcy, Debra A. Fischer, Jason T. Wright, Gregory W. Henry, Matthew J. Giguere, Howard Isaacson, Jeff A. Valenti,… 展开作者
Andrew W. Howard, John A. Johnson, Geoffrey W. Marcy, Debra A. Fischer, Jason T. Wright, Gregory W. Henry, Matthew J. Giguere, Howard Isaacson, Jeff A. Valenti, Jay Anderson, Nikolai E. Piskunov
我们报告了NASA-UC Eta-Earth计划中发现的第一颗低质量行星，这是一颗围绕K 0矮星HD 7924运行的超级地球。开普勒模型的精确多普勒径向速度揭示了一个行星的最小质量M_Psin i = 9.26 M_地球在一个P = 5.398 d的轨道。根据2001年至2008年的测量数据，该行星被稳健地探测到，估计误报概率小于0.001。使用费尔伯恩天文台的自动测光望远镜进行的测光观测显示HD 7924在径向速度期间的光度常数为0.19毫等，支持行星伴星的存在。在测光极限~0.5毫等以下，没有发现凌日现象，排除了各种成分的凌日行星。HD 7924 b是已知的仅有的八颗M_P sin i < 10 M_地球的行星之一，因此是一个新兴的低质量行星家族的成员，这些行星共同限制了行星形成的理论。
英文摘要：
We report the discovery of the first low-mass planet to emerge from the NASA-UC Eta-Earth Program, a super-Earth orbiting the K0 dwarf HD 7924. Keplerian modeling of precise Doppler radial velocities reveals a planet with minimum mass M_P sin i = 9.26 M_Earth in a P = 5.398 d orbit. Based on Keck-HIRES measurements from 2001 to 2008, the planet is robustly detected with an estimated false alarm probability of less than 0.001. Photometric observations using the Automated Photometric Telescopes at Fairborn Observatory show that HD 7924 is photometrically constant over the radial velocity period to 0.19 mmag, supporting the existence of the planetary companion. No transits were detected down to a photometric limit of ~0.5 mmag, eliminating transiting planets with a variety of compositions. HD 7924b is one of only eight planets known with M_P sin i < 10 M_Earth and as such is a member of an emerging family of low-mass planets that together constrain theories of planet formation.
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NASA Decadal Astrobiology Research and Exploration Strategy (NASA-DARES 2025) White Paper -- Habitable Worlds Observatory Living Worlds Science Cases: Research Gaps and Needs
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