Welcome to the NOAA Institutional Repository | Sunspot numbers, 1610-1985 : based on "The sunspot activity in the years 1610-1960" - :1344 | National Environmental Satellite and Data Information Service (NESDIS)
Stacks Logo
Advanced Search
Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.
 
 
Help
Clear All Simple Search
Advanced Search
Sunspot numbers, 1610-1985 : based on "The sunspot activity in the years 1610-1960"
  • Published Date:
    1987
Filetype[PDF - 6.71 MB]


This document cannot be previewed automatically as it exceeds 5 MB
Please click the thumbnail image to view the document.
Sunspot numbers, 1610-1985 : based on
Details:
  • Personal Authors:
  • Corporate Authors:
    United States, National Environmental Satellite, Data, and Information Service, ; World Data Center A for Solar-Terrestrial Physics ;
  • Series:
    Report UAG ; 95
  • Document Type:
  • Description:
    "In 1848 the Swiss astronomer Johann Rudolph Wolf introduced the sunspot number index--an estimate of the number of spots visible on one hemisphere of the sun. The observation consists of a daily count over the solar disk of the number of spots (regardless of size) and of the number of groups into which the cluster. Rudolph Wolf arbitrarily defined his daily sunspot number as the total spot count added to 10 times the number of spot groups, because neither the number of groups nor the number of spots alone adequately measured the activity. Counting only groups would ignore their great variation in size, since some can contain more than 100 single spots, while others, only a few. Counting only individual spots, on the other hand, would ignore their unequal rank, because spots appearing within an existing group have less significance than ones emerging where none existed before"--Introduction.

  • Supporting Files:
    No Additional Files