Daily Sunspot Evaluation
Observation Sheet Friday, 13 September 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)
- 12
- Number of spots (f)
- 116
- Relative number (R)
- 236
- Observer
- AT
- Reading
- all checks consistent
- File
- 19680913.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | ? – 1 | 21 | 79E | 332 | |||
| 2 | A – 1 | 16 | 30E | 21 | |||
| 3 | C – 7 | 7 | 30E | 21 | |||
| 4 | A – 4 | -11 | 40E | 11 | |||
| 5 | H – 41 | -13 | 22E | 29 | |||
| 6 | A – 1 | -21 | 23E | 28 | |||
| 7 | E – 16 | -12 | 24W | 75 | |||
| 8 | D – 17 | -19 | 32W | 83 | |||
| 9 | D – 19 | -21 | 41W | 92 | |||
| 10 | A – 5 | -15 | 54W | 105 | |||
| 11 | A – 3 | 13 | 41W | 92 | |||
| 12 | A – 1 | 12 | 62W | 113 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.