Daily Sunspot Evaluation
Observation Sheet Wednesday, 1 April 1981
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)
- 13
- Number of spots (f)
- 69
- Relative number (R)
- 199
- Observer
- GT
- Reading
- all checks consistent
- File
- 19810401.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | HSX – 1 | 22 | 54W | 99 | 57W | 2 | |
| 2 | DAC – 13 | 26 | 23E | 22 | 20E | 8 | |
| 3 | DAC – 15 | 13 | 25E | 20 | 22E | 6 | |
| 4 | HSX – 1 | 4 | 26E | 19 | 23E | 1 | |
| 5 | HSX – 1 | 10 | 33E | 12 | 30E | 1 | |
| 6 | CAO – 2 | 18 | 58E | 347 | 55E | 55 | |
| 7 | ? – 1 | 7 | 75E | 330 | 72E | 2.5 | |
| 8 | CAO – 4 | -16 | 75W | 120 | 78W | 9 | |
| 9 | HKC – 14 | -43 | 54W | 99 | 75W | 10 | |
| 10 | HSX – 1 | -11 | 24W | 69 | 27W | 1.5 | |
| 11 | CSI – 6 | -11 | 17E | 28 | 14E | 3 | |
| 12 | HAX – 4 | -4 | 34E | 11 | 31E | 2 | |
| 13 | BXI – 6 | -15 | 71E | 334 | 68E | 6 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.