Daily Sunspot Evaluation
Observation Sheet Thursday, 17 April 1980
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)
- 8
- Number of spots (f)
- 78
- Relative number (R)
- 158
- Observer
- TÖ
- Reading
- all checks consistent
- File
- 19800417.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | DAI – 12 | 19 | 10W | 342 | 13W | 9 | |
| 2 | DAI – 13 | 14 | 06W | 338 | 09W | 10.5 | |
| 3 | DSI – 19 | -29 | 03W | 335 | 06W | 10.5 | |
| 4 | DAO – 7 | -17 | 68E | 264 | 65E | 10 | |
| 5 | DAO – 2 | -21 | 66W | 38 | 69W | 3 | |
| 6 | DAO – 3 | -30 | 52W | 24 | 55W | 5 | |
| 7 | EKI – 19 | -8 | 41W | 13 | 44W | 13.5 | |
| 8 | BXX – 3 | -32 | 37W | 9 | 40W | 4.5 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.