Daily Sunspot Evaluation
Observation Sheet Tuesday, 17 December 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)
- 7
- Number of spots (f)
- 64
- Relative number (R)
- 134
- Observer
- HÇ0
- Reading
- all checks consistent
- File
- 19911217.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | FKC – 22 | 9 | 58W | 306 | 60W | 16 | 670 |
| 2 | BRI – 6 | 21 | 36W | 284 | 38W | 5 | 671 |
| 3 | AX – 1 | -33 | 65W | 313 | 69W | - | 622 |
| 4 | DAI – 13 | -17 | 21W | 269 | 23W | 7 | 681 |
| 5 | CHO – 5 | -4 | 19W | 267 | 21W | 9 | 678 |
| 6 | CAO – 8 | -18 | 00 | 248 | 02W | 9.5 | 675 |
| 7 | EKI – 9 | -11 | 58E | 190 | 56E | 15 | 680 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.