Daily Sunspot Evaluation
Observation Sheet Tuesday, 18 December 1990
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)
- 4
- Number of spots (f)
- 79
- Relative number (R)
- 119
- Observer
- SG0
- Reading
- all checks consistent
- File
- 19901218.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | CKO – 15 | 4 | 35W | 48 | 38W | 17 | 570 |
| 2 | DKC – 22 | 13 | 20W | 33 | 23W | 7 | 574 |
| 3 | FKI – 33 | 17 | 06W | 19 | 09W | 19 | 575 |
| 4 | DAI – 9 | -5 | 07E | 6 | 04E | 5 | 579 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.