Daily Sunspot Evaluation
Observation Sheet Friday, 13 September 1974
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)
- 38
- Relative number (R)
- 78
- Observer
- SK
- Reading
- counts consistent, some coordinates doubtful
- File
- 19740913.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | H – 16 | 9 | 27E | 266 | |||
| 2 | C – 19 | -13 | 28E | 265 | |||
| 3 | J – 1 | -16 | 39W | 254 ⚠ | |||
| 4 | J – 2 | -3 | 54W | 347 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.