Daily Sunspot Evaluation
Observation Sheet Wednesday, 28 July 1971
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)
- 7
- Number of spots (f)
- 40
- Relative number (R)
- 110
- Observer
- HA
- Reading
- all checks consistent
- File
- 19710728.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | J – 4 | 4 | 69E | 188 | |||
| 2 | H – 10 | -13 | 27E | 230 | |||
| 3 | J – 1 | -7 | 14E | 243 | |||
| 4 | C – 9 | -13 | 17W | 274 | |||
| 5 | D – 9 | 12 | 54W | 311 | |||
| 6 | A – 2 | 18 | 53W | 310 | |||
| 7 | A – 5 | 23 | 41W | 298 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.