Daily Sunspot Evaluation
Observation Sheet Tuesday, 28 September 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)
- 41
- Relative number (R)
- 81
- Observer
- MA
- Reading
- all checks consistent
- File
- 19710928.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | ? – 4 | 11 | 84E | 77 | |||
| 2 | C – 26 | -6 | 43E | 118 | |||
| 3 | H – 1 | -6 | 29E | 132 | |||
| 4 | C – 10 | -14 | 30W | 191 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.