Solar Activity Database


National Astronomical Observatory of Japan and its predecessor (Tokyo Astronomic al Observatory of the University of Tokyo) have been conducting observations of various activity indices of the sun. The peak of solar activity, indicated by numerous sunspots and frequent flare ex plosions, comes every 10-11 years. This periodicity is sometimes disturbed; for example in the 17-th century there was a period of about 50 years in which the solar activity was unusually low. In order to investigate such a long time scale variation of the sun, persistent observations of the sun and systematic accumulation of data are crucial.
We have made the following data available to the public. No restrictions apply for browsing the data. When you intend to publish an article based on these data, you are requested to contact us in advance.

Database Calendar


Solar Flare Telescope
Observing Status, 1992--
Solar Telescopes
White-Light Full-Disk Continuum,G-band Full-Disk Image, 2012-- Sunspot Relative Numbers, 1929--& Area, 1998--
Sunspot Drawings, 1938--1998
Polar Faculae, 1951--1998
White-Light Full-Disk Image, 1918--1998
White-Light Full-Disk Image, 1998--
CaK Full-Disk CaK Full-Disk Images, 2015-- CaK Full-Disk Images, 1917--1974
Hα Full-Disk Hα Full-Disk Images, 2011-- Hα Full-Disk Images, 1949--2019
Hα Flare Images, 1958--2002
He 10830Å Full-Disk Magnetograms Infrared Stokes-Polarization Full-Disk Images, 2010-- Norikura 25cm Coronagraph Images, 1991--1998
Full-Disk Magnetograms Infrared Stokes-Polarization Full-Disk Images, 2010-- STEP Full-Disk Magnetograph Images, 1993--2011
Active Region Vector Magnetograms Vector Magnetogram Images,1992--2007 Photoelectric Vector Magnetograph Images, Okayama Observatory, 1982--1995
Hα Active Region Hα Active Region Images, 1992--2007
5303Å Coronal Green-Line Intensities Norikura 10cm Coronagraph Intensities, 1951--2009
Coronagraph Norikura 10cm Coronagraph Images, 1978--2009
10cm Coronagraph Images, after transfered to Yunnan, China, 2013— (operated by Yunnan Observatory, NAOC)
STEP/S-RAMP Solar Optical Data On-Line
CAWSES Solar Optical Data On-Line
Solar Activity World Data Center
Quarterly Bulletin on Solar Activity (QBSA)
Sunspot Groups with Largest Areas (1874-2016)