Observed abundance ratios [X/H]_GCE in HIP 68468 as a function of condensation temperature (red circles). The abundances are corrected for galactic chemical evolution to the Sun’s age. Planet engulfment of 6 Earth masses of rocky material (blue triangles) can explain the enhancement of refractory elements. The mean abundance trend of 11 solar twins relative to the Sun (Meléndez et al. 2009) is shown by the dashed line.