Daily Sunspot Evaluation
Observation Sheet Friday, 13 December 1968
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)
- 4
- Number of spots (f)
- 31
- Relative number (R)
- 71
- Observer
- AT
- Reading
- all checks consistent
- File
- 19681213.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | A – 4 | -23 | 65E | 226 | |||
| 2 | E – 22 | -34 | 04E | 287 | |||
| 3 | A – 3 | 17 | 66W | 357 | |||
| 4 | J – 2 | 18 | 50W | 341 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.