Daily Sunspot Evaluation
Observation Sheet Thursday, 12 September 1957
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)
- 12
- Number of spots (f)
- 151
- Relative number (R)
- 271
- Observer
- ET
- Reading
- all checks consistent
- File
- 19570912.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | B – 10 | 24 | 23E | ||||
| 2 | J – 4 | 16 | 66E | ||||
| 3 | A – 1 | 11 | 72E | ||||
| 4 | J – 2 | -25 | 58E | ||||
| 5 | H – 5 | -20 | 25E | ||||
| 6 | D – 12 | -44 | 23E | ||||
| 7 | E – 30 | -16 | X2WE | ||||
| 8 | E – 15 | -13 | 22W | ||||
| 9 | C – 13 | -8 | 40WEE | ||||
| 10 | ? – 13 | -24 | 63W | ||||
| 11 | A – 6 | 13 | 46W | ||||
| 12 | E – 40 | 12 | 20WE |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.



