Daily Sunspot Evaluation
Observation Sheet Thursday, 13 August 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)
- 8
- Number of spots (f)
- 66
- Relative number (R)
- 146
- Observer
- AÖ0
- Reading
- all checks consistent
- File
- 19810813.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | HKX – 1 | 11 | 54W | 128 | 57W | 3 | |
| 2 | HAX – 5 | 26 | 16W | 90 | 19W | 2 | |
| 3 | DAI – 7 | -24 | 71W | 145 | 74W | 13 | |
| 4 | FKC – 34 | -8 | 47W | 121 | 50W | 20 | |
| 5 | ARX – 2 | -16 | 42W | 116 | 45W | 1 | |
| 6 | ARX – 1 | -11 | 14W | 88 | 17W | 2 | |
| 7 | BXO – 3 | -20 | 51E | 23 | 48E | 35 | |
| 8 | FKC – 13 | -16 | 70E | 4 | 67E | 15 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.