Daily Sunspot Evaluation
Observation Sheet Thursday, 21 May 1970
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)
- 11
- Number of spots (f)
- 70
- Relative number (R)
- 180
- Observer
- MA
- Reading
- all checks consistent
- File
- 19700521.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | H – 11 | 16 | 14E | 199 | |||
| 2 | A – 3 | 11 | 16E | 197 | |||
| 3 | C – 6 | 14 | 50E | 163 | |||
| 4 | J – 1 | 16 | 69E | 144 | |||
| 5 | B – 4 | -8 | 03E | 210 | |||
| 6 | A – 1 | -15 | 24W | 237 | |||
| 7 | C – 12 | -9 | 27W | 240 | |||
| 8 | J – 1 | -10 | 63W | 276 | |||
| 9 | J – 1 | -6 | 66W | 279 | |||
| 10 | F – 29 | 20 | 42W | 255 | |||
| 11 | A – 1 | 6 | 03W | 216 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.