Daily Sunspot Evaluation
Observation Sheet Tuesday, 20 February 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)
- 4
- Number of spots (f)
- 15
- Relative number (R)
- 55
- Observer
- FA
- Reading
- all checks consistent
- File
- 19730220.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | J – 4 | -16 | 03W | 262 | 33 | ||
| 2 | D – 8 | -17 | 47W | 306 | 25 | ||
| 3 | A – 2 | -13 | 50W | 309 | 34 | ||
| 4 | A – 1 | 8 | 72W | 331 | 32 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.