CV-Helios Network
CV-USAF project

The CV-USAF project was established in 2003,
in order to study and compare the work of classifications observed by CV-Helios Network from August 1981 until present
with Joint NOAA/USAF observational data performed from October 1966 until present.

Complete Sunspotregions 1981-2017 Distribution Classifications Distribution mvh classifications
Sunspotregions >1000 mvh Listing annual classifications  
Sunspotregions graphics Sunspotregions per month  
Sunspotregions complete Z/McI-cls.
Sunspotregions complete Z/McI-cls.
NOAA/USAF (graphics & tables)
Sunspotregions' individual frequencies