Daily Sunspot Evaluation
Observation Sheet Friday, 13 December 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)
- 10
- Number of spots (f)
- 50
- Relative number (R)
- 150
- Observer
- ET
- Reading
- all checks consistent
- File
- 19571213.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | A – 3 | 22 | 35 | ||||
| 2 | B – 9 | -13 | 38 | ||||
| 3 | ? – 4 | -15 | 78 | ||||
| 4 | A – 1 | -25 | 57 | ||||
| 5 | A – 1 | -22 | 48 | ||||
| 6 | A – 2 | -19 | 39 | ||||
| 7 | A – 3 | -28 | 1 | ||||
| 8 | A – 1 | -12 | 3 | ||||
| 9 | G – 2 | -20 | 45 | ||||
| 10 | E – 24 | 10 | 29 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.