This year has given stargazers plenty of opportunities to catch the colorful auroras of the northern lights flicker across the night sky, and that's expected to continue as the sun is now in its solar maximum – the peak of its 11-year solar cycle.

One way to track the solar cycle is by counting the number of sunspots, which are dark, cooler patches on the Sun’s surface. Such cycles have been tracked by astronomers since Galileo first observed sunspots in the 1600s.

Cosmogenic radionuclides, such as 14C and 10Be, are produced in Earth’s atmosphere by interactions with cosmic rays and offer a unique window into past solar variability. Their deposition in natural archives – notably tree rings and ice cores ...

Massive solar flares, graceful eruptions of solar material, and an enormous sunspot make up some of the imagery captured by NASA's Solar Dynamics Observatory in 2013 and 2014. A year ago this weekend, the sun’s activity created some of the most ...