Daily Sunspot Evaluation
Observation Sheet Thursday, 12 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)
- 7
- Number of spots (f)
- 31
- Relative number (R)
- 101
- Observer
- HM
- Reading
- all checks consistent
- File
- 19740912.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | H – 12 | 7 | 41E | 266 | |||
| 2 | C – 10 | -13 | 42E | 265 | |||
| 3 | J – 1 | -16 | 52E | 255 | |||
| 4 | A – 1 | -13 | 60W | 7 | |||
| 5 | J – 2 | -3 | 40W | 347 | |||
| 6 | J – 1 | -8 | 75W | 22 | |||
| 7 | G – 4 | 8 | 73W | 20 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.