Daily Sunspot Evaluation
Observation Sheet Monday, 18 September 1961
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)
- 4
- Number of spots (f)
- 30
- Relative number (R)
- 70
- Observer
- PO
- Reading
- all checks consistent
- File
- 19610918.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | J – 1 | 13 | 43E | ||||
| 2 | B – 8 | -9 | 39W | ||||
| 3 | C – 8 | -9 | 52W | ||||
| 4 | E – 13 | 10 | 28W |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.