Daily Sunspot Evaluation
Observation Sheet Monday, 18 February 1991
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)
- 15
- Number of spots (f)
- 76
- Relative number (R)
- 226
- Observer
- YK
- Reading
- all checks consistent
- File
- 19910218.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | AX – 1 | 25 | 19W | 295 | 21W | 65 | |
| 2 | CAI – 9 | 24 | 09W | 285 | 11W | 4.5 | 64 |
| 3 | BXI – 6 | 29 | 50E | 226 | 48E | 4.5 | 77 |
| 4 | HA – 2 | -13 | 76W | 352 | 78W | 3 | 74 |
| 5 | HA – 3 | -8 | 72W | 348 | 74W | 5 | 66 |
| 6 | AR – 5 | -24 | 68W | 344 | 70W | 5 | 81 |
| 7 | AX – 1 | -12 | 55W | 331 | 57W | 67 | |
| 8 | AR – 1 | -4 | 48W | 324 | 50W | 0.5 | 68 |
| 9 | CAI – 9 | -13 | 13E | 263 | 11E | 4.5 | 78 |
| 10 | BXI – 11 | -17 | 19E | 257 | 17E | 5 | 76 |
| 11 | AR – 2 | -13 | 27E | 249 | 25E | 1.5 | 82 |
| 12 | DKI – 17 | -17 | 47E | 229 | 45E | 7.5 | 79 |
| 13 | BRO – 2 | -4 | 54E | 222 | 52E | 4.5 | 83 |
| 14 | ? – 5 | -21 | 80E | 196 | 78E | 84 | |
| 15 | ? – 2 | -13 | 81E | 195 | 79E | 85 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.