论文标题
我们最近的陆地星球维纳斯的亮度调制揭示了大气上的超级旋转，而不是表面特征
Brightness modulations of our nearest terrestrial planet Venus reveal atmospheric super-rotation rather than surface features
论文作者
论文摘要
在其宿主恒星居住区内或附近绕行的陆生外行星可能符合生命。已经提出，从此类行星中反射的星光的时间序列测量将揭示其旋转周期，主表面特征和一些大气信息。从Akatsuki航天器获得的图像中，我们在这里表明，金星的亮度为283、365和2020 nm，由3.7和4.6天的两个周期中的一个或两个调节，典型的振幅<10％，但偶尔发生的事件为20-40％。调制与实体旋转无关。它们是由叠加在超旋转风中的行星尺度波引起的。在这里，我们提出两个调制时期的大于大小值的比例不是整数的数字，如果在外部球星处检测到大气的存在，但是无论大气在光学上还是较厚，无论是地球还是金星，它仍然含糊不清。可能需要多波长和较长的时间基线观测值才能在这些情况之间做出决定。最终，金星代表着对陆地系外行星亮度调制的解释的假阳性。
Terrestrial exoplanets orbiting within or near their host stars' habitable zone are potentially apt for life. It has been proposed that time-series measurements of reflected starlight from such planets will reveal their rotational period, main surface features and some atmospheric information. From imagery obtained with the Akatsuki spacecraft, here we show that Venus' brightness at 283, 365, and 2020 nm is modulated by one or both of two periods of 3.7 and 4.6 days, and typical amplitudes <10% but occasional events of 20-40%. The modulations are unrelated to the solid-body rotation; they are caused by planetary-scale waves superimposed on the super-rotating winds. Here we propose that two modulation periods whose ratio of large-to-small values is not an integer number imply the existence of an atmosphere if detected at an exoplanet, but it remains ambiguous whether the atmosphere is optically thin or thick, as for Earth or Venus respectively. Multi-wavelength and long temporal baseline observations may be required to decide between these scenarios. Ultimately, Venus represents a false positive for interpretations of brightness modulations of terrestrial exoplanets in terms of surface features.
