Daily Sunspot Evaluation
Observation Sheet Sunday, 13 December 1987
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)
- 2
- Number of spots (f)
- 3
- Relative number (R)
- 23
- Observer
- AÖ0
- Reading
- all checks consistent
- File
- 19871213.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | ARX – 2 | -26 | 40E | 104 | 38E | 3 | 100 |
| 2 | HAX – 1 | -33 | 76E | 69 | 73E | 2.25 | 101 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.