Daily Sunspot Evaluation
Observation Sheet Thursday, 22 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)
- 8
- Number of spots (f)
- 39
- Relative number (R)
- 119
- Observer
- HA
- Reading
- all checks consistent
- File
- 19710422.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | A – 1 | -17 | 68E | 35 | |||
| 2 | B – 11 | -10 | 36W | 139 | |||
| 3 | J – 2 | -7 | 73W | 176 | |||
| 4 | J – 1 | 1 | 79W | 182 | |||
| 5 | H – 3 | 8 | 56W | 159 | |||
| 6 | D – 11 | 17 | 58W | 161 | |||
| 7 | J – 1 | 16 | 50W | 153 | |||
| 8 | J – 9 | 20 | 44W | 147 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.