Daily Sunspot Evaluation
Observation Sheet Friday, 18 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)
- 3
- Number of spots (f)
- 9
- Relative number (R)
- 39
- Observer
- HG
- Reading
- all checks consistent
- File
- 19871218.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | BRO – 2 | 22 | 63E | 15 | 61E | 4.5 | 102 |
| 2 | ARX – 1 | -26 | 30W | 108 | 32W | - | 100 |
| 3 | EAF – 6 | -33 | 15E | 63 | 13E | 11 | 101 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.