Daily Sunspot Evaluation
Observation Sheet Saturday, 18 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)
- 8
- Number of spots (f)
- 45
- Relative number (R)
- 125
- Observer
- MA
- Reading
- all checks consistent
- File
- 19710918.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | A – 2 | 13 | 01°E | 292 | |||
| 2 | H – 6 | 4 | 13°E | 280 | |||
| 3 | A – 1 | -2 | 50°E | 243 | |||
| 4 | A – 3 | -6 | 63°E | 230 | |||
| 5 | A – 3 | -13 | 25°E | 268 | |||
| 6 | E – 25 | -12 | 14°E | 279 | |||
| 7 | C – 4 | -16 | 67°W | 0 | |||
| 8 | J – 1 | 12 | 26°W | 319 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.