The Gist of Science Reporter: October 2016
Content:
- Solar Tantrums (Free Available)
- Fly a Solar Plane! (Only For The Subscribed Members)
Solar Tantrums
The Sun is an active star. It undergoes a cycle of 11 years (solar cycle) which involves changes ill the Sun s activity (including changes in the levels of solar radiation and ejection of solar material) and appearance (changes in the number of sunspots, flares, and other manifestations). The sunspot number is one of the first and most visible signs of the solar activity cycle.
About 400 years ago, Italian scientist Galileo observed spots on the Sun and found that the Sun rotates around its own axis in -25 days. In 1621, he also observed mysterious lights in the night sky, which he termed as “Aurora” after the Roman Goddess of Light. Solar Wind and Aurora depend on the sunspot number. In a cycle of 11 years, the sunspot number goes from a minimum to a maximum. These cycles are now numbered. The present cycle is the 24th.
When the sunspot number becomes very low (close to zero), these periods are called “Minimum” and after about 5-6 years the sunspot number becomes large, at times as high as 200 - these periods are called “Maximum”. The light and total energy fr m the Sun also changes, but this variation is only ~0.1%.