Daily Sunspot Evaluation
Observation Sheet Wednesday, 15 September 1971
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)
- 51
- Relative number (R)
- 121
- Observer
- MA
- Reading
- all checks consistent
- File
- 19710915.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | J – 1 | 12 | 13E | 319 | |||
| 2 | A – 2 | 13 | 41E | 291 | |||
| 3 | H – 1 | 4 | 53E | 279 | |||
| 4 | E – 28 | -12 | 56E | 276 | |||
| 5 | A – 7 | -13 | 65E | 267 | |||
| 6 | C – 11 | -16 | 30W | 2 | |||
| 7 | A – 1 | 5 | 53W | 25 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.