Daily Sunspot Evaluation
Observation Sheet Thursday, 21 May 1981
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)
- 31
- Relative number (R)
- 91
- Observer
- TÖ
- Reading
- all checks consistent
- File
- 19810521.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | FAO – 9 | 13 | 51W | 156 | 54W | 24.5 | |
| 2 | HAX – 4 | -28 | 60W | 165 | 63W | 3 | |
| 3 | AXX – 1 | -9 | 43W | 148 | 46W | ||
| 4 | HKI – 15 | -24 | 12W | 117 | 15W | 5.5 | |
| 5 | AXX – 1 | -12 | 61E | 44 | 58E | ||
| 6 | ARX – 1 | -9 | 69E | 36 | 66E | 1.5 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.