Daily Sunspot Evaluation
Observation Sheet Thursday, 17 April 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)
- 11
- Number of spots (f)
- 59
- Relative number (R)
- 169
- Observer
- WG
- Reading
- all checks consistent
- File
- 19580417.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | A – 1 | 40 | 12E | ||||
| 2 | J – 1 | 39 | 47E | ||||
| 3 | B – 4 | 21 | 27E | ||||
| 4 | C – 4 | 17 | 23E | ||||
| 5 | ? – 1 | 14 | 85E | ||||
| 6 | A – 3 | -9 | 71E | ||||
| 7 | E – 26 | -21 | 50E | ||||
| 8 | B – 9 | -10 | 59W | ||||
| 9 | A – 5 | 14 | 45W | ||||
| 10 | B – 3 | 8 | 28W | ||||
| 11 | B – 2 | 20 | 28W |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.