Daily Sunspot Evaluation
Observation Sheet Thursday, 18 September 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)
- 15
- Number of spots (f)
- 160
- Relative number (R)
- 310
- Observer
- FY
- Reading
- all checks consistent
- File
- 19580918.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | C – 21 | 22 | 26E | ||||
| 2 | B – 7 | 12 | 59E | ||||
| 3 | A – 1 | 7 | 41E | ||||
| 4 | A – 1 | -19 | 42E | ||||
| 5 | F – 59 | -18 | 13E | ||||
| 6 | A – 1 | -20 | 2W | ||||
| 7 | H – 4 | -13 | 6W | ||||
| 8 | G – 9 | -32 | 21W | ||||
| 9 | A – 1 | -29 | 31W | ||||
| 10 | B – 10 | -22 | 62W | ||||
| 11 | D – 15 | -10 | 51W | ||||
| 12 | A – 1 | -7 | 45W | ||||
| 13 | H – 3 | 14 | 23W | ||||
| 14 | B – 4 | 28 | 25W | ||||
| 15 | C – 23 | 18 | 12W |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.