“This year was supposed to be the year of ‘solar maximum,’ the peak of the 11-year sunspot cycle.
But … solar activity is relatively low.
‘Sunspot numbers are well below their values from 2011, and strong solar flares have been infrequent,’ the space agency says.
[The Helioseismic and Magnetic Imager (HMI) on NASA's Solar Dynamics Observatory] observed just a few small sunspots on an otherwise clean face, which is usually riddled with many spots during peak solar activity.
Solar physicist Dean Pesnell of NASA’s Goddard Space Flight Center believes he has a different explanation.
‘This is solar maximum,’ he says.
‘But it looks different from what we expected because it is double-peaked.’
‘The last two solar maxima, around 1989 and 2001, had not one but two peaks.’
Solar activity went up, dipped, then rose again, performing a mini-cycle that lasted about two years, he said.