Daily Sunspot Evaluation
Observation Sheet Thursday, 18 September 1969
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)
- 68
- Relative number (R)
- 178
- Observer
- LT
- Reading
- all checks consistent
- File
- 19690918.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | B – 3 | 11 | 57°E | 151 | |||
| 2 | A – 1 | 1 | 39°E | 169 | |||
| 3 | A – 1 | -4 | 02°W | 216 | |||
| 4 | B – 8 | -11 | 05°W | 213 | |||
| 5 | C – 30 | -6 | 13°W | 221 | |||
| 6 | A – 1 | -13 | 23°W | 231 | |||
| 7 | J – 3 | -13 | 35°W | 217 | |||
| 8 | A – 2 | -11 | 39°W | 217 | |||
| 9 | A – 2 | -5 | 42°W | 250 | |||
| 10 | D – 10 | 7 | 55°W | 263 | |||
| 11 | G – 7 | 14 | 27°W | 235 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.