Active Prominences on a Quiet Sun  
 
Image Credit &
Copyright:
Alan Friedman
(Averted Imagination)
  
 Explanation:  
Why is the Sun so quiet?
As the Sun enters into a period of time known as a 
Solar Minimum, it is, as expected, showing fewer 
sunspots and 
active regions than usual.
The quietness is somewhat unsettling, though, as so far this year, most days show no sunspots at all.
In contrast, from 2011 - 2015, during 
Solar Maximum, 
the Sun displayed spots just about every day. 
Maxima and minima occur on an 
11-year cycle, with the 
last Solar Minimum 
being the most quiet in a century. 
Will this current Solar Minimum 
go even deeper?
Even though the 
Sun's activity affects the Earth and its surroundings, 
no one knows for sure 
what the Sun will do next, 
and the physics behind the processes remain an 
active topic of research. 
The 
featured image was taken 
three weeks ago and shows that our Sun is busy even on a quiet day.
Prominences of hot 
plasma, 
some larger than the Earth, 
dance continually and are most easily visible over the edge. 
Source: NASA