Daily Sunspot Evaluation
Observation Sheet Wednesday, 18 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)
- 6
- Number of spots (f)
- 49
- Relative number (R)
- 109
- Observer
- GT
- Reading
- all checks consistent
- File
- 19810218.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | DAC – 21 | 19 | 28E | 209 | 27E | 8.8 | |
| 2 | HKX – 2 | 11 | 24E | 213 | 23E | 4 | |
| 3 | DAC – 15 | 12 | 13E | 224 | 12E | 7 | |
| 4 | HSX – 1 | 15 | 02E | 235 | 01E | 2.5 | |
| 5 | HAX – 2 | 13 | 56W | 293 | 57W | 1.5 | |
| 6 | DAO – 8 | -19 | 18E | 219 | 17E | 3.5 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.