Daily Sunspot Evaluation
Observation Sheet Sunday, 17 December 1972
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)
- 16
- Relative number (R)
- 56
- Observer
- HM
- Reading
- all checks consistent
- File
- 19721217.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | J – 2 | 16 | 53E | 340 | |||
| 2 | D – 3 | 0 | 40E | 353 | |||
| 3 | E – 9 | -19 | 27W | 60 | |||
| 4 | H – 2 | 11 | 74W | 107 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.