Daily Sunspot Evaluation
Observation Sheet Monday, 17 December 1990
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)
- 5
- Number of spots (f)
- 57
- Relative number (R)
- 107
- Observer
- TÖ0
- Reading
- all checks consistent
- File
- 19901217.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | CAI – 14 | 4 | 23W | 48 | 24W | 15 | 570 |
| 2 | DAC – 12 | 13 | 08W | 33 | 09W | 5 | 574 |
| 3 | AX – 1 | 23 | 07W | 32 | 08W | — | 578 |
| 4 | FKC – 21 | 17 | 05E | 20 | 04E | 18 | 575 |
| 5 | BRI – 9 | -5 | 18E | 7 | 17E | 4.5 | 579 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.