Daily Sunspot Evaluation
Observation Sheet Friday, 17 April 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)
- 21
- Relative number (R)
- 41
- Observer
- HG
- Reading
- all checks consistent
- File
- 19870417.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | HAX – 2 | -7 | 51W | 127 | 54W | 2 | 15 |
| 2 | EKC – 19 | -31 | 54W | 130 | 57W | 13 | 16 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.