Daily Sunspot Evaluation
Observation Sheet Sunday, 20 June 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)
- 4
- Number of spots (f)
- 13
- Relative number (R)
- 53
- Observer
- SM
- Reading
- all checks consistent
- File
- 19710620.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | C – 7 | 10 | 59E | 343 | |||
| 2 | A – 2 | -19 | 50E | 352 | |||
| 3 | A – 1 | -11 | 07E | 35 | |||
| 4 | B – 3 | -6 | 34W | 76 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.