Daily Sunspot Evaluation
Observation Sheet Friday, 23 April 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)
- 20
- Relative number (R)
- 80
- Observer
- LT
- Reading
- all checks consistent
- File
- 19710423.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | A – 1 | -19 | 57E | 33 | |||
| 2 | B – 6 | -10 | 49W | 139 | |||
| 3 | J – 2 | 4 | 66W | 156 | |||
| 4 | H – 1 | 9 | 71W | 161 | |||
| 5 | G – 8 | 17 | 69W | 159 | |||
| 6 | A – 2 | 21 | 58W | 148 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.