Daily Sunspot Evaluation
Observation Sheet Tuesday, 17 August 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)
- 6
- Number of spots (f)
- 21
- Relative number (R)
- 81
- Observer
- MA
- Reading
- all checks consistent
- File
- 19710817.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | J – 2 | 14 | 02E | 354 | |||
| 2 | A – 1 | 14 | 12E | 344 | |||
| 3 | J – 2 | 17 | 63E | 293 | |||
| 4 | H – 2 | 13 | 39E | 317 | |||
| 5 | ? – 1 | -13 | 84E | 272 | |||
| 6 | B – 13 | -14 | 20W | 16 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.