Daily Sunspot Evaluation
Observation Sheet Tuesday, 18 February 1958
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)
- 13
- Number of spots (f)
- 28
- Relative number (R)
- 158
- Observer
- AK
- Reading
- all checks consistent
- File
- 19580218.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | A – 2 | 20 | 32E | ||||
| 2 | C – 3 | -13 | 73E | ||||
| 3 | H – 1 | -15 | 50E | ||||
| 4 | C – 7 | -15 | 31E | ||||
| 5 | A – 1 | -18 | 49E | ||||
| 6 | J – 1 | -24 | 64E | ||||
| 7 | A – 1 | -14 | 1E | ||||
| 8 | J – 1 | -14 | 5W | ||||
| 9 | E – 4 | 11 | 68W | ||||
| 10 | A – 1 | 21 | 61W | ||||
| 11 | A – 2 | 12 | 35W | ||||
| 12 | J – 1 | 23 | 7W | ||||
| 13 | C – 3 | 5 | 1W |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.