Limaye Sanjay S
Space Science and Engineering Center, University of Wisconsin-Madison, Madison, WI 53706, USA.
Life (Basel). 2025 Apr 29;15(5):717. doi: 10.3390/life15050717.
Venus is not generally at the forefront when considering extraterrestrial life. Yet, based on the physical similarities and proximity to Earth and with the little knowledge of its evolutionary history, there is a possibility that Venus may have hosted life in the past on the surface if Venus had liquid water and perhaps even has water present in the clouds today. While the early suggestions during the beginning of the space exploration about life on Venus were mostly speculative due to limited data, recent interest has arisen from realizations: (i) the unexplained ultraviolet absorption spectrum of Venus resembles many organics, (ii) there is chemical disequilibria in the cloud layer, (iii) the cloud aerosols likely contain significant abundances of hydrated iron and magnesium sulfates, and (iv) the solar radiation received in the cloud layer contains the appropriate wavelengths and flux to support phototrophy. Considering the extreme environmental survival of many terrestrial microorganisms, the possibility remains that any extant life on Venus in the past could have adapted to survival in the cloud layer far above the surface where energy and nutrients are available, but the precise compositions of the cloud particles and water availability are still uncertain. The key to solving the mystery of life on Venus is to determine if Venus had liquid water on the surface in its past and to measure the precise chemical composition of the Venus atmosphere and the cloud particles. Missions which will be launched in the next few years will provide much needed data that should provide some answers we seek and will surely raise more questions. This perspective reviews recent developments.
在考虑外星生命时，金星通常并不处于前沿位置。然而，基于与地球的物理相似性和相近距离，以及对其演化历史的了解甚少，如果金星过去有液态水，甚至如今云层中也有水存在，那么金星过去在其表面有可能存在过生命。虽然在太空探索初期，由于数据有限，关于金星上生命的早期推测大多是猜测性的，但最近人们产生了兴趣，原因如下：（i）金星无法解释的紫外线吸收光谱与许多有机物相似；（ii）云层中存在化学不平衡；（iii）云气溶胶可能含有大量的水合铁和硫酸镁；（iv）云层接收到的太阳辐射包含支持光合作用的适当波长和通量。考虑到许多陆地微生物能在极端环境中生存，过去金星上任何现存的生命都有可能适应在远高于表面的云层中生存，那里有能量和营养物质，但云粒子的精确组成和水的可利用性仍然不确定。解开金星生命之谜的关键在于确定金星过去表面是否有液态水，以及测量金星大气和云粒子的精确化学成分。未来几年即将发射的任务将提供急需的数据，这些数据应该能提供我们所寻求的一些答案，同时肯定也会引发更多问题。本观点综述了近期的进展。
