EASTERN ACTIVITY: A phalanx of sunspots is rotating over the sun’s eastern limb, and this could bring an uptick in solar activity. “Today the sun looks alive again with lots of sunspots and magnetic filaments rising over the sun’s eastern edge,” reports amateur astronomer Sergio Castillo, who sends this picture from Inglewood, California:

Castillo took the picture using a solar telescope capped with a Ca K filter tuned to the light of singly-ionized calcium. Ca K (“calcium K”) filters are particularly good at revealing the magnetic froth around active sunspots; pictured above is sunspot complex 1614-1615.

fr/spaceweather.com