SWPC/GEOMAG/A
From ViRBO
See also SWPC#A and K Indices.
A index
- Updated hourly.
- Data are derived from ftp://ftp.swpc.noaa.gov/pub/lists/geomag/YYYYMMDDAK.txt files. Click this link if the date in the drop-down menu below appears outdated; you may also need to clear your browser's cache.
