Scientists are narrowing the search for the unidentified material causing dark patterns in Venus’s clouds, a mystery observed for a century. Researchers calculated how strongly the substance must absorb light, refining possibilities for its composition. The study, led by Dr. Jan Spacek, used radiative-transfer modeling and compared observations of Venus to how a concentrated sample of the cloud material might appear in a laboratory setting.
Venus appears pale yellow in visible light, but exhibits dark and bright features in ultraviolet wavelengths within its sulfuric acid clouds. The substance responsible for these patterns, termed the “unknown absorber,” has remained unidentified for approximately 100 years. An international team of researchers has now established numerical limits on the characteristics of this material.
The team combined observations of Venus with a radiative-transfer model to estimate the level of ultraviolet and blue light absorption needed to match observed patterns. Dr. Jan Spacek of the Foundation for Applied Molecular Evolution, USA, explained the approach: “Our model effectively asks what would happen if we could collect that cloud material into a cuvette and put it into a laboratory spectrometer.” He emphasized that light absorption in a bulk liquid can correlate with the concentration of light-absorbing material in a solution.
The researchers drew a comparison to cigarette smoke, noting that while it appears white due to light scattering, collected particles form a dark, tar-like sludge. This suggests Venus’s pale yellow clouds could contain a surprisingly dark liquid. The study, published in *Astrobiology*, measured how strongly the mystery material absorbs light by tracking light scattering and absorption by cloud droplets and atmospheric molecules.
Read the original coverage
💬 Comments
📜 Comment Policy