Daily Sunspot Evaluation
Observation Sheet Tuesday, 17 February 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)
- 7
- Number of spots (f)
- 78
- Relative number (R)
- 148
- Observer
- AÖ0
- Reading
- all checks consistent
- File
- 19810217.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | ? – 5 | 11 | 77W | 328 | 79W | ||
| 2 | EKC – 29 | 19 | 09W | 260 | 11W | 13.5 | |
| 3 | HKX – 3 | 11 | 09W | 260 | 11W | 3.5 | |
| 4 | DKC – 16 | 12 | 03E | 248 | 01E | 6 | |
| 5 | DKO – 7 | 15 | 16E | 235 | 14E | 9 | |
| 6 | AXX – 2 | 13 | 71E | 180 | 69E | ||
| 7 | DAI – 16 | -20 | 04W | 255 | 06W | 7 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.