Discovery and exploration of the Solar System as clouds, dust storms, and ice caps on the other planets. The first exploration of the Solar System was conducted by telescope, when astronomers first began to map those objects too faint to be seen with the naked eye. Galileo was the first to discover physical details about the individual bodies of the Solar System. He discovered that the Moon was cratered, that the Sun was marked with sunspots, and that Jupiter had four satellites in orbit around it. Christiaan Huygens followed on from Galileo's discoveries by discovering Saturn's moon Titan and the shape of the rings of Saturn. Giovanni
Solar cycle 24 to trigger a radio blackout. Larger than the planet Jupiter, the AR 12192 sunspot was visible during a partial solar eclipse seen in North America. The sun emitted a mid-level solar flare, an M7.9-class, peaking at 4:16 a.m. EDT on June 25, 2015. In early November 2015, solar flares disrupted the air traffic control system in central and southern Sweden, causing heavy delays for passengers. A sunspot group originally attributed to the new solar cycle 25 is observed. The sunspot numbers continue to decline. During 2016, there were 26 days with no sunspots (preliminary numbers). As of 31 March, preliminary