WORLD NEWS
Venus’s dark cloud markings require an exceptionally strong absorber
Venus has an unknown material that darkens ultraviolet and blue cloud patterns. After accounting for known gases and droplet scattering, the model required a peak coefficient of 1,278 cm−1 at 375 nm.
This is an inferred bulk-liquid property, not a directly measured molecule or concentration. Organic examples are possible, but identity, biological origin and life remain unconfirmed.
Why scattering matters
Tiny droplets can look bright while containing dark liquid. The study inverted 365–455 nm reflectance using droplet size, altitude and gas absorption.
Meaning of 1,278
It is a base-10 coefficient for a hypothetical 1-cm liquid path. Real droplets and light paths are much smaller and more complicated.
Candidates
A representative porphyrin-like pigment would need roughly 12 g/L; weaker inorganic absorbers would need to be major aerosol components. Mixtures could fit too.
Importance
The unknown absorber takes up more than half the solar energy reaching the cloud-top atmosphere, affecting heating and circulation.
Next
The model covers 365–455 nm and an assumed 6-km layer. In-situ composition and spectra are needed to distinguish candidates.
Primary source and independent checks
Read in other languages
한국어 · English · Español · 日本語 · Tiếng Việt