Daily Sunspot Evaluation
Observation Sheet Friday, 28 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)
- 31
- Relative number (R)
- 91
- Observer
- ET
- Reading
- all checks consistent
- File
- 19510928.jpg
Sunspot groups
| No | Group (class – spots) | r | p | Margin no. |
|---|---|---|---|---|
| 1 | B – 10 | 0.43 | 80 | |
| 2 | A – 1 | 0.04 | 139 | |
| 3 | A – 1 | 0.46 | 145 | |
| 4 | C – 11 | 0.88 | 302 | |
| 5 | ? – 5 | 0.96 | 303 | |
| 6 | ? – 3 | 0.97 | 309 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.