Daily Sunspot Evaluation
Observation Sheet Thursday, 31 July 1975
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)
- 3
- Number of spots (f)
- 20
- Relative number (R)
- 50
- Observer
- GA
- Reading
- all checks consistent
- File
- 19750731.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | C – 12 | 4 | 70E | 307 | 67E | ||
| 2 | J – 1 | 8 | 52W | 69 | 55W | ||
| 3 | H – 7 | 9 | 72W | 89 | 75W |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.