sunspot maximum

sunspot maximum

[′sən‚spät ′mak·sə·məm]
(astronomy)
The time in the solar cycle when the number of sunspots reaches a maximum value.
References in periodicals archive ?
The peak of North Dakotan auroral activity appears to take place after sunspot maximum and when the spots are declining.
As for those fierce solar storms, the next sunspot maximum will not happen until 2013, and will be on the mild side, astronomers now say.
The last sunspot maximum (peak of activity) was in 2000, and the next one is expected in 2011.
During the sunspot maximum, the solar magnetic field is disrupted by solar flares (extremely large explosions) emitting solar ultraviolet light, x-rays, energetic particles (million-electron-volt protons), coronal mass ejections (high temperature plasma gases which give a ring-like appearance around the sun or any other celestial body), and a "stormy" solar wind.
Although the researchers made their discovery using high-resolution images from the Atmospheric Imaging Assembly aboard the Solar Dynamics Observatory (SDO), they also observed the cells on ultraviolet images from STEREO-A and -B spacecraft recently, and from the Solar and Heliospheric Observatory (SOHO) in 2000 near the previous sunspot maximum.
The comparatively low level of solar activity this close to the predicted sunspot maximum next year, seems to confirm that we are indeed experiencing a low activity solar cycle.