Daily Sunspot Evaluation
Observation Sheet Thursday, 16 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)
- 115
- Relative number (R)
- 245
- Observer
- TÖ
- Reading
- all checks consistent
- File
- 19810416.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | ? – 2 | 1 | 85W | 293 | 88W | ||
| 2 | AXX – 1 | 6 | 65W | 273 | 68W | ||
| 3 | EXC – 27 | 14 | 24W | 232 | 27W | 13 E | |
| 4 | DXO – 18 | 9 | 11W | 219 | 14W | 5.75 E | |
| 5 | CAI – 10 | 14 | 01E | 207 | 02W | 5° | |
| 6 | CAI – 9 | 23 | 35E | 173 | 32E | 10.75 | |
| 7 | CAI – 9 | 18 | 35E | 173 | 32E | 6 | |
| 8 | DRC – 14 | 14 | 56E | 152 | 53E | 7.75 | |
| 9 | DAO – 5 | 25 | 61E | 147 | 58E | 8 | |
| 10 | ARX – 3 | -5 | 27W | 237 | 32W | 0.5 | |
| 11 | HAX – 1 | -4 | 15W | 223 | 18W | 0.5 | |
| 12 | DHC – 15 | -8 | 16E | 192 | 13E | 9.75 | |
| 13 | HAX – 1 | -10 | 60E | 148 | 57E | 2 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.