Researchers calculate numerical limits for unknown light absorber in Venus's clouds

The short version

• Modeling shows Venus's unknown cloud absorber must absorb light strongly, reaching an absorption coefficient of roughly 1,278 cm-1 at 375 nm.[ScienceDaily]
• The results challenge many proposed inorganic candidates because they would require very high concentrations to match observed absorption.[ScienceDaily]
• The findings do not prove that life exists on Venus or verify whether the absorbing substance is organic or inorganic.[ScienceDaily]
• A planned Rocket Lab mission intends to use an Autofluorescence Nephelometer to search Venusian cloud particles for organic fluorescence.[ScienceDaily]

Key facts

• Dark and bright ultraviolet patterns in Venus's upper sulfuric acid clouds have remained unexplained for roughly a century.[ScienceDaily]
• Radiative-transfer modeling calculated that the cloud droplet liquid requires a decadic absorption coefficient of about 1,278 cm-1 at 375 nm.[ScienceDaily]
• Molecules with absorption properties similar to porphyrinoid pigments would need to be present at approximately 10 grams per liter.[ScienceDaily]
• An Autofluorescence Nephelometer is scheduled to fly on a Rocket Lab mission to search for fluorescence linked to organic molecules.[ScienceDaily]

Sources

Outlet counts describe coverage, not independent confirmation. Reports may share a wire service or original source.

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