Daily Sunspot Evaluation
Observation Sheet Monday, 17 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)
- 6
- Number of spots (f)
- 47
- Relative number (R)
- 107
- Observer
- MH
- Reading
- all checks consistent
- File
- 19510917.jpg
Sunspot groups
| No | Group (class – spots) | r | p | Margin no. |
|---|---|---|---|---|
| 1 | D – 13 | 0.61 | 102 | |
| 2 | A – 2 | 0.16 | 104 | |
| 3 | J – 1 | 0.56 | 244 | |
| 4 | C – 6 | 0.63 | 295 | |
| 5 | C – 24 | 0.45 | 298 | |
| 6 | A – 1 | 0.7 | 313 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.