Speaker
Description
The Sunspot Number series, with its almost 420 years of data, is one of the longest and most detailed available series in astrophysics, it is produced and maintained at the World Data Center SILSO (https://sidc.be/SILSO/home). Since 2010, eJorts have been undertaken by the solar community to revise both the Sunspot Number and the Group Number series (SN and GN). After an extensive recalibration in 2015, the historical series still suJers from various scale discrepancies which only a complete reconstruction will solve (Clette et al., 2016, 2023). I will present the latest news and plans for the near future.
Tests have been made on the techniques to reconstruct the Sunspot Number from 1814 to 1944 (Bhattacharya et al. 2023, 2024), while the historical data available has been sorted in a database and quality controlled (FARSUN, https://sidc.be/farsun). A summary of the available reconstruction techniques will be presented.
Progress of the SILSO part of the Belgian SUNRISE project will be presented. Launched in 2023, SUNRISE will modernize the day-to-day computation of the SN, and add the production, at the same frequency, of the GN (Belgian SUNRISE project).
In summary, in 2027, a historical database centralizing all available sunspot data (number of groups and spots when available) will be put into action, and will keep being updated as new data is digitized. During the same timeline, the production of the SN will be modernized and GN will be produced by the WDC-SILSO with the same frequency as SN. Combining the above historical and modern updates, new major versions of SN and GN will be released with complete transparency as to their construction.