Daily Sunspot Evaluation
Observation Sheet Thursday, 13 May 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)
- 9
- Number of spots (f)
- 43
- Relative number (R)
- 133
- Observer
- HA
- Reading
- all checks consistent
- File
- 19710513.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | A – 1 | 5 | 21E | 165 | |||
| 2 | C – 6 | 2 | 29E | 159 | |||
| 3 | H – 12 | 5 | 56E | 130 | |||
| 4 | B – 3 | -10 | 06E | 180 | |||
| 5 | ? – 1 | 11 | 80W | 266 | |||
| 6 | J – 2 | 11 | 69W | 255 | |||
| 7 | A – 1 | 5 | 08W | 194 | |||
| 8 | C – 14 | 18 | 07W | 193 | |||
| 9 | J – 3 | 3 | 01W | 187 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.