Daily Sunspot Evaluation
Observation Sheet Thursday, 13 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)
- 11
- Number of spots (f)
- 48
- Relative number (R)
- 158
- Observer
- TA
- Reading
- all checks consistent
- File
- 19901213.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | ? – 1 | 22 | 85W | 164 | 87W | 2 | 558 |
| 2 | CKI – 3 | 9 | 66W | 145 | 68W | 10 | 561 |
| 3 | AX – 2 | 19 | 66W | 145 | 68W | 2 | 560 |
| 4 | HA – 2 | 28 | 24E | 55 | 22E | 1.5 | 569 |
| 5 | CKI – 20 | 5 | 29E | 50 | 27E | 11 | 590 |
| 6 | AR – 1 | 10 | 45E | 34 | 43E | 1 | 594 |
| 7 | HA – 2 | 22 | 46E | 33 | 44E | 2 | 593 |
| 8 | FKO – 13 | 18 | 60E | 19 | 58E | 20 | 595 |
| 9 | HA – 1 | -18 | 60W | 139 | 62W | 1.5 | 566 |
| 10 | BXO – 2 | -24 | 20E | 59 | 18E | 5 | 592 |
| 11 | AX – 1 | -25 | 60E | 19 | 58E | - | 596 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.