  The elemental composition in the coronae of low-activity solar-like stars
appears to be related to fundamental stellar properties such as rotation,
surface gravity, and spectral type. Here we use full-Sun observations from the
Solar Dynamics Observatory, to show that when the Sun is observed as a star,
the variation of coronal composition is highly correlated with a proxy for
solar activity, the F10.7 cm radio flux, and therefore with the solar cycle
phase. Similar cyclic variations should therefore be detectable
spectroscopically in X-ray observations of solar analogs. The plasma
composition in full-disk observations of the Sun is related to the evolution of
coronal magnetic field activity. Our observations therefore introduce an
uncertainty into the nature of any relationship between coronal composition and
fixed stellar properties. The results highlight the importance of systematic
full-cycle observations for understanding the elemental composition of
solar-like stellar coronae.
