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Photo-evaporation of planetary atmospheres plays a key role in the evolution of exoplanets comma carving their whole population. However comma direct observations of atmospheric escape are scarce and almost non-existent in the mass range of super-Earths and mini-Neptunes comma while these planets are among the most impacted by the phenomenon. A huge step forward could be made by achieving a comparative study of several super-Earths comma volatile-rich or not comma in a single multi-planet systemdoublePoint such planets would indeed experience the same evolution of the stellar X and EUV flux that are driving atmospheric escape. The perfect system for such a study has just been identifieddoublePoint the nearby comma solar-type comma and naked-eye star nuelev2 Lupi hosts transiting planets spanning a remarkably large range of insolation (virgul100 to virgul5x the insolation of Earth). TESS found the transits of the two inner planets and CHEOPS detected the transit of planet d comma a volatile-rich super-Earth with an exceptional period of 107 day. These super-Earths straddle the radius gap of the d_commaevaporation valleyd_comma and could have retained different fractions of gas and volatiles. Like for previously observed warm Neptunes comma they could be enshrouded in huge comet-like exospheric clouds of escaping gas comma which could have built up in the mild radiative environment. The system unique combination of proximity comma brightness and favorable planet characteristics offers a fantastic opportunity to exploit HST ultraviolet capabilities to search for the hydrogen comma oxygen and carbon escaping three planets in whole new mass and irradiation regimes. It is the ideal testbed for advancing both observations and theories of atmospheric evaporation of exoplanets.

行星大气的光蒸发（photo-evaporation）在系外行星的演化中扮演关键角色，塑造了其整体种群结构。然而，在超级地球（super-Earth）和迷你海王星（mini-Neptune）的质量范围内，大气逃逸的直接观测极为稀少，几乎不存在，而这些行星恰恰是受该现象影响最显著的群体之一。若能在单一多行星系统中对若干超级地球（无论富挥发分与否）开展比较研究，将有望取得重大进展：这些行星确实会经历驱动大气逃逸的恒星X射线和极紫外（EUV）辐射通量的相同演化过程。此类研究的理想系统刚被发现：邻近的、类太阳的肉眼可见恒星ν² Lupi拥有凌星行星，其接收到的辐照量范围极广（约为地球辐照量的100倍至5倍）。凌日系外行星勘测卫星（Transiting Exoplanet Survey Satellite, TESS）发现了两颗内行星的凌星现象，而系外行星特征卫星（Characterising Exoplanet Satellite, CHEOPS）则探测到了行星d的凌星——这是一颗富挥发分的超级地球，其公转周期长达107天，颇为特殊。这些超级地球跨越了d-蒸发谷（d-evaporation valley）的半径间隙，可能保留了不同比例的气体和挥发分。与此前观测到的温暖海王星类似，它们可能被巨大的彗星状逃逸气体外层云所笼罩，这些云或许是在温和的辐射环境中形成的。该系统兼具邻近性、高亮度及有利的行星特征，为利用哈勃空间望远镜（Hubble Space Telescope, HST）的紫外探测能力，在全新的质量和辐照环境下搜寻三颗行星的逃逸氢、氧和碳元素提供了绝佳机遇。它是推进系外行星大气蒸发观测与理论研究的理想试验平台。