Daily total sunspot number --------------------------- Time range: 1/1/1818 - 31/05/2015 Data description: Daily total sunspot number derived by the formula: R= 0.6 (Ns + 10 * Ng), with Ns the number of spots and Ng the number of groups counted over the entire solar disk. The 0.6 scaling factor was determined to bring the modern counts to the scale of the original sunspot index derived by Rudolph Wolf in the mid-19th century. By definition, the index cannot take values between 0 (no spots) and 7 (single solitary spot, R=0.6*11). No daily data are provided before 1818 because daily observations become too sparse in earlier years. Therefore, R. Wolf only compiled monthly means and yearly means for all years before 1818. NB: The TXT files below are identical except for the placeholder for missing days (?,999 or NaN) In the CSV file, the missing values are marked by -1 (the sunspot number itself is always positive). ------------------------------------------------------------------------------- TXT 1 ------------------------------------------------------------------------------- Filename: dayssn.dat Format: plain ASCII text Contents: Column 1: Gregorian calendar date Column 2: Date in fraction of year Column 3: Daily total sunspot number. A '?' symbol replaces the value when none is available for that day. Column 4: Definitive/provisional marker. A blank indicates that the value is definitive. A '*' symbol indicates that the value is still provisional and is subject to a possible revision (Usually the last 3 to 6 months) Line format [character position]: - [1-4] Year - [5-6] Month - [7-8] Day - [11-18] Decimal date - [20-22] Daily sunspot number - [24] Definitive/provisional indicator ------------------------------------------------------------------------------- TXT 2 ------------------------------------------------------------------------------- Filename: dayssnv0.dat Format: plain ASCII text Contents: Column 1: Gregorian calendar date Column 2: Date in fraction of year Column 3: Daily total sunspot number. A '999' dummy value replaces the value when none is available for that day. Column 4: Definitive/provisional marker. A blank indicates that the value is definitive. A '*' symbol indicates that the value is still provisional and is subject to a possible revision (Usually the last 3 to 6 months) Line format [character position]: - [1-4] Year - [5-6] Month - [7-8] Day - [11-18] Decimal date - [20-22] daily sunspot number - [24] Definitive/provisional indicator ------------------------------------------------------------------------------- TXT 3 ------------------------------------------------------------------------------- Filename: dayssn_import.dat Format: plain ASCII text Contents: Columns 1 : Gregorian calendar date Column 2 : Date in fraction of year Column 3 : Daily total sunspot number. A 'NaN' entry replaces the value when none is available for that day. Column 4 : Definitive/provisional marker. A blank indicates that the value is definitive. A '*' symbol indicates that the value is still provisional and is subject to a possible revision (Usually the last 2 or 3 months) Line format [character position]: - [1-4] Year - [5-6] Month - [7-8] Day - [11-18] Decimal date - [20-22] Daily sunspot number - [24] Definitive/provisional indicator ------------------------------------------------------------------------------- CSV ------------------------------------------------------------------------------- Filename: ISSN_D_tot.csv Format: Comma Separated values (adapted for import e.g. in MS Excel) Contents: Column 1-3: Gregorian calendar date - Year - Month - Day Column 4: Date in fraction of year Column 3: Daily total sunspot number. A value of -1 indicates that no number is available for that day (missing value). Column 4: Definitive/provisional indicator. '1' indicates that the value is definitive. '0' indicates that the value is still provisional and is subject to a possible revision (Usually the last 2 or 3 months)