Daily Sunspot Evaluation
Observation Sheet Sunday, 16 September 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)
- 10
- Number of spots (f)
- 54
- Relative number (R)
- 154
- Observer
- ET
- Reading
- all checks consistent
- File
- 19510916.jpg
Sunspot groups
| No | Group (class – spots) | r | p | Margin no. |
|---|---|---|---|---|
| 1 | D – 11 | 0.36 | 102 | |
| 2 | A – 1 | 0.47 | 103 | |
| 3 | J – 1 | 0.36 | 110 | |
| 4 | A – 2 | 0.34 | 207 | |
| 5 | A – 2 | 0.35 | 218 | |
| 6 | J – 3 | 0.47 | 225 | |
| 7 | J – 2 | 0.46 | 293 | |
| 8 | C – 29 | 0.27 | 297 | |
| 9 | A – 1 | 0.46 | 311 | |
| 10 | A – 2 | 0.54 | 315 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.