Daily Sunspot Evaluation
Observation Sheet Friday, 21 December 1973
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)
- 28
- Relative number (R)
- 58
- Observer
- FA
- Reading
- counts consistent, some coordinates doubtful
- File
- 19731221.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | J – 2 | 7 | 05E | 200 | 221 | ||
| 2 | E – 25 | -18 | 13E | 132 ⚠ | 222 | ||
| 3 | A – 1 | -15 | 13W | 218 | 223 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.