Fig. 1.

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200-yr span of sunspot numbers places current observations in a wider perspective (top). Around activity minima, days without reported sunspots are not unusual. Recent Cycle 24 with daily sunspot numbers (bottom) from WDC-SILSO (World Data Center – Sunspot Index and Long-term Solar Observations, Royal Observatory of Belgium, Brussels). Superposed red curve shows monthly averages. The selected periods from which HARPS-N data were analyzed are marked with vertical bars.
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