Daily Sunspot Evaluation
Observation Sheet Tuesday, 21 April 1970
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)
- 38
- Relative number (R)
- 98
- Observer
- SM
- Reading
- all checks consistent
- File
- 19700421.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | C – 4 | 20 | 33E | 221 | |||
| 2 | A – 2 | 20 | 39E | 215 | |||
| 3 | B – 12 | -9 | 24E | 230 | |||
| 4 | G – 9 | -7 | 22W | 276 | |||
| 5 | B – 7 | 2 | 22W | 276 | |||
| 6 | B – 4 | 16 | 11W | 265 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.