Daily Sunspot Evaluation
Observation Sheet Monday, 20 May 1991
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)
- 12
- Number of spots (f)
- 57
- Relative number (R)
- 177
- Observer
- SG0
- Reading
- all checks consistent
- File
- 19910520.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | ? – 1 | 9 | 80W | 236 | 83W | 2 | 215 |
| 2 | AX – 1 | 17 | 53W | 209 | 56W | 233 | |
| 3 | BXO – 4 | 14 | 50W | 206 | 53W | 10 | 230 |
| 4 | CAI – 12 | 17 | 16E | 140 | 13E | 7 | 234 |
| 5 | ? – 1 | -18 | 76W | 232 | 79W | 2 | 216 |
| 6 | ? – 4 | -9 | 73W | 229 | 76W | 9.5 | 229 |
| 7 | AX – 2 | -10 | 45W | 201 | 48W | 2 | 235 |
| 8 | AX – 4 | -26 | 25W | 181 | 28W | 1 | 236 |
| 9 | BRO – 10 | -29 | 04E | 152 | 01E | 7 | 237 |
| 10 | EAC – 13 | -12 | 09E | 147 | 06E | 12.5 | 232 |
| 11 | HA – 4 | -29 | 53E | 103 | 50E | 3.5 | 238 |
| 12 | AX – 1 | -25 | 72E | 84 | 69E | 239 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.