Daily Sunspot Evaluation
Observation Sheet Friday, 20 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)
- 8
- Number of spots (f)
- 31
- Relative number (R)
- 111
- Observer
- TÖ
- Reading
- all checks consistent
- File
- 19810220.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | DAC – 7 | 13 | 54W | 265 | 56W | 9 | |
| 2 | DAO – 2 | 11 | 47W | 258 | 49W | 8.5 | |
| 3 | DAO – 2 | 14 | 31W | 242 | 33W | 9 | |
| 4 | DAC – 11 | 11 | 15E | 196 | 13E | 7.5 | |
| 5 | HSX – 1 | 13 | 28E | 182 | 26E | 1.25 | |
| 6 | DAI – 5 | -6 | 48W | 259 | 50W | 7.5 | |
| 7 | HAX – 1 | -13 | 48W | 259 | 50W | 1 | |
| 8 | HKX – 2 | -17 | 78E | 132 | 76E |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.