Daily Sunspot Evaluation
Observation Sheet Tuesday, 31 March 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)
- 11
- Number of spots (f)
- 51
- Relative number (R)
- 161
- Observer
- SM
- Reading
- all checks consistent
- File
- 19810331.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | CAI – 6 | 22 | 41W | 99 | 43W | 4 | |
| 2 | AXX – 1 | 17 | 14E | 44 | 12E | ||
| 3 | DAC – 7 | 26 | 35E | 23 | 33E | 9.5 | |
| 4 | BXO – 2 | 4 | 38E | 20 | 36E | 2 | |
| 5 | CAI – 10 | 13 | 39E | 19 | 37E | 6 | |
| 6 | AXX – 1 | 10 | 46E | 12 | 44E | ||
| 7 | HAX – 2 | 19 | 71E | 347 | 69E | 5 | |
| 8 | CAI – 7 | -16 | 63W | 121 | 65W | 9.5 | |
| 9 | HKC – 12 | -44 | 41W | 99 | 43W | 8 | |
| 10 | HSX – 1 | -11 | 11W | 69 | 13W | 1.25 | |
| 11 | HAX – 2 | -3 | 46E | 12 | 44E | 2.5 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.