Daily Sunspot Evaluation
Observation Sheet Friday, 20 August 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)
- 6
- Number of spots (f)
- 79
- Relative number (R)
- 139
- Observer
- MA
- Reading
- all checks consistent
- File
- 19710820.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | B – 11 | 18 | 23E | 293 | |||
| 2 | F – 54 | -12 | 48E | 268 | |||
| 3 | J – 5 | -16 | 62W | 18 | |||
| 4 | B – 6 | 10 | 40W | 356 | |||
| 5 | A – 1 | 14 | 29W | 345 | |||
| 6 | H – 2 | 13 | 01W | 317 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.