Daily Sunspot Evaluation
Observation Sheet Friday, 31 July 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)
- 10
- Number of spots (f)
- 125
- Relative number (R)
- 225
- Observer
- AÖ0
- Reading
- all checks consistent
- File
- 19810731.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | DAI – 19 | 13 | 31W | 276 | 34W | 11.5 | |
| 2 | AXX – 1 | 18 | 09W | 254 | 12W | ||
| 3 | CAI – 8 | 18 | 28E | 217 | 25E | 8 | |
| 4 | DAI – 22 | 15 | 30E | 215 | 27E | 9.5 | |
| 5 | BXO – 2 | -6 | 71W | 316 | 74W | 4.5 | |
| 6 | FKC – 62 | -10 | 44W | 289 | 47W | 26 | |
| 7 | HSX – 1 | -19 | 39W | 284 | 42W | 2 | |
| 8 | HSX – 2 | -2 | 29W | 274 | 32W | 2 | |
| 9 | AXX – 2 | -18 | 11W | 256 | 14W | 2 | |
| 10 | CAI – 6 | -5 | 06W | 251 | 09W | 5 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.