Daily Sunspot Evaluation
Observation Sheet Saturday, 21 April 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)
- 7
- Number of spots (f)
- 92
- Relative number (R)
- 162
- Observer
- WG
- Reading
- all checks consistent
- File
- 19510421.jpg
Sunspot groups
| No | Group (class – spots) | r | p | Margin no. |
|---|---|---|---|---|
| 1 | A – 6 | 0.32 | 15 | |
| 2 | ? – 2 | 0.94 | 44 | |
| 3 | A – 8 | 0.68 | 75 | |
| 4 | B – 7 | 0.7 | 80 | |
| 5 | A – 1 | 0.62 | 234 | |
| 6 | J – 2 | 0.85 | 241 | |
| 7 | F – 66 | 0.6 | 270 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.