AI 中文总结
利用ExPo观测金星反射太阳光偏振通量中的同心环，因仪器拆除无法确定成因。数值模拟显示可能因重力波致云层上方气体密度变化产生偏振环，总通量观测无此现象，希望推动新的偏振观测证实或反驳。
AI 中文摘要
我们报告了2010年在威廉·赫歇尔望远镜上使用高灵敏度的极端偏振仪（ExPo）进行的一次偶然的36分钟观测中，对金星反射的太阳光偏振通量中微弱（$10^{-6}$）、同心、全行星范围的环的观测结果。这些环似乎以太阳直射点的下风方向为中心，在可见光的不同滤光片中可见，而在同时进行的总通量观测中不明显。ExPo的双光束交换和双差分设计强烈抑制了一阶仪器偏振，我们无法确定观测到的图案的仪器原因。由于在数据中识别出这些环之前ExPo已被拆除，这是这些环的唯一一组观测数据。因此，我们在声称探测到金星上一种新的大气现象时很谨慎。然而数值辐射传输模拟表明，由于云层上方气体中5%至10%的密度变化，可能会出现全行星范围的偏振环，这与重力波一致。我们的模拟还表明，这种密度变化在总通量观测中不会出现。通过展示我们的观测和数值模拟，我们希望推动对金星进行新的偏振观测，以证实或反驳这种全行星范围波的存在。
英文摘要
We report observations of faint ($10^{-6}$), concentric, planet-wide rings in the polarized flux of sunlight that is reflected by Venus, obtained during a serendipitous, 36-minute run in 2010, with the highly sensitive Extreme Polarimeter (ExPo) on the William Herschel Telescope. The rings appear to be centered slightly downwind of the sub-solar point, are visible in different filters across the visible, and are not obvious in the simultaneous total flux observations. ExPo's dual-beam exchange and double-differencing design strongly suppresses first-order instrumental polarization, and we could not identify an instrumental cause of the observed pattern. Because ExPo was dismantled before the rings were identified in the data, this is the only set of observations of these rings. We are therefore careful in claiming the detection of a new atmospheric phenomenon on Venus. However, numerical radiative transfer simulations show that planet-wide rings in polarization can arise due to density variations of 5 to 10% in the gas above the clouds, consistent with a gravity wave. Our simulations also show that such density variations would not show up in total flux observations. By presenting our observations and numerical simulations, we hope to motivate new polarimetric observations of Venus that could confirm or refute the presence of such planet-wide waves.
Comments19 pages, 11 figures. Published in The Planetary Science Journal
Journal refThe Planetary Science Journal, 7, 169 (2026)
