Daily Sunspot Evaluation
Observation Sheet Thursday, 21 June 1951
There is no typed record for this day. The values below were read by computer from the table on the sheet; when in doubt, see the drawing. Details →
- Number of groups (g)
- 5
- Number of spots (f)
- 98
- Relative number (R)
- 148
- Observer
- WG
- Reading
- all checks consistent
- File
- 19510621.jpg
Sunspot groups
| No | Group (class – spots) | r | p | Margin no. |
|---|---|---|---|---|
| 1 | C – 7 | 0.4 | 45 | |
| 2 | ? – 1 | 0.98 | 74 | |
| 3 | J – 1 | 0.73 | 114 | |
| 4 | F – 84 | 0.62 | 242 | |
| 5 | C – 5 | 0.5 | 295 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.