The Sun was blank more than 89% of the time from June 22 - September 22, with only 6 brief and tiny sunspots and not a single significant solar flare during this period of extreme quiet, Dr. Tony Phillips of the SpaceWeather reports.
"This is a sign that Solar Minimum is underway and probably near its deepest point," Dr. Phillips said.
"For 2019 overall (January through September), the Sun has been blank 72% of the time, comparable to annual averages during the century-class Solar Minimum of 2008 (73%) and 2009 (71%). The current Solar Minimum appears to be century-class as well, meaning you have to go back to the beginning of the 20th century to find lulls in solar activity this deep."
During the Solar Minimum phase of the solar cycle, sunspot and flare activity diminishes, the Sun's magnetic field weakens, allowing cosmic rays to enter the solar system; streams of solar wind punch through the Sun's weakening magnetic field, lashing Earth with gaseous material that can cause geomagnetic storms; the Sun also dims, especially at extreme ultraviolet wavelengths, causing the upper atmosphere to cool and collapse.
Featured image credit: SIDC/SILSO