V889 Herculis is a young Sun that is rotating fast enough (Prot = 1.337 days) for mapping its
surface by the means of Doppler Imaging. The 10 FOCES spectra collected between 13-16 Aug 2006
at Calar Alto Observatory allowed us to reconstruct one single Doppler image for two mapping lines
(Fe I-6411 and Ca I-6439).
Applying the sheared-image method with our Doppler reconstruction code TempMap
we perform an investigation to detect surface differential rotation (DR). The resulting surface shear
(1% of solar type) is compared to previous studies which reported either much stronger shear
or comparably weak DR, or just preferred rigid rotation. Theoretical aspects are also considered
and discussed.
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