What is Solar Maximum? | NASA Goddard FriendsofNASA.org: The Sun is stirring from its latest slumber. As sunspots and flares bubble from the Sun’s surface, representatives from NASA, the National Oceanic and Atmospheric Agency (NOAA), and the Solar Cycle Prediction Panel have announced the Sun has reached its solar maximum period. The solar cycle is the natural cycle of the Sun as it transitions between low and high activity. During the most active part of the cycle, known as solar maximum, the