The long-standing mystery surrounding the 'unknown ultraviolet (UV) absorber' in Venus's dense atmosphere may be closer to a solution, with recent scientific investigations strongly pointing to ferric chloride (FeCl3) and other iron-sulfur compounds as key candidates. For decades, scientists have observed dark streaks in Venus's clouds that efficiently absorb UV radiation, impacting the planet's energy balance and climate. Identifying this absorber is crucial for understanding Venus's atmospheric chemistry and evolution. Multiple credible sources corroborate the role of iron-bearing compounds. A study by Egan, James, and Plane, published in ACS Earth and Space Chemistry, presented laboratory measurements of ferric chloride in concentrated sulfuric acid under Venusian conditions. Their findings demonstrated that the absorption spectrum of FeCl3 closely matches observations of the unknown UV absorber, suggesting it could largely explain the phenomenon if present in sufficient concentrations. The research also highlighted the importance of considering ferric sulfate (Fe2(SO4)3), which can form from FeCl3 in sulfuric acid and absorbs strongly below 320 nm, to avoid misattributing absorption to sulfur dioxide. Concurrently, research by Jiang et al., published in Science Advances, explored iron-sulfur chemistry, synthesizing minerals like rhomboclase and acid ferric sulfate. Their spectroscopic analysis revealed that a combination of these two minerals, along with dissolved ferric iron, could also account for the observed UV and blue light absorption in the Venusian clouds. These studies underscore the complexity of Venus's atmospheric chemistry, proposing a rich, unexplored heterogeneous chemistry within cloud droplets. The source of iron in Venus's atmosphere is an ongoing area of study, with possibilities including volcanic activity, surface dust, or interplanetary cosmic dust. A re-analysis of data from NASA's 1978 Pioneer Venus mission even suggested that Venusian cloud aerosols contain significant amounts of water and iron sulfate, potentially brought in by cosmic dust, further supporting the presence of iron compounds in the upper atmosphere. While sulfur allotropes and other sulfur compounds have also been proposed as contributors to the UV absorption, the recent experimental evidence strongly solidifies the candidacy of ferric chloride and related iron-sulfur minerals. These findings are critical for future missions to Venus, such as DAVINCI, which aim to further unravel the planet's atmospheric composition.