Daily Sunspot Evaluation
Observation Sheet Thursday, 21 August 1975
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)
- 11
- Relative number (R)
- 51
- Observer
- SK
- Reading
- all checks consistent
- File
- 19750821.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | A – 2 | 8 | 06E | 92 | 05E | ||
| 2 | B – 2 | 8 | 19E | 79 | 18E | ||
| 3 | A – 1 | -5 | 73W | 171 | 74W | ||
| 4 | ? – 6 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.