Measurements of the helium 584Â Ã airglow during the Cassini flyby of Venus

► The distribution of the HeI resonance line at 584 Å was measured with UVIS during the flyby of Venus by Cassini. ► The mean disk intensity was ∼320 R and the bright limb reached ∼700 R. ► The sensitivity of the 584 Å intensity to the helium abundance has been analyzed using a radiative transfer model. ► We find very good agreement with the observations for the helium density distribution from the VTS3 empirical model. ► Our values are larger than previous remote sensing determinations by a factor of about 2.