Daily Sunspot Evaluation
Observation Sheet Sunday, 18 April 1999
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)
- 6
- Number of spots (f)
- 31
- Relative number (R)
- 91
- Observer
- TA
- Reading
- all checks consistent
- File
- 19990418.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | AX – 3 | 16 | 73W | 244 | 75W | 3 | |
| 2 | DRS – 10 | 21 | 42W | 213 | 44W | 7 | |
| 3 | AX – 1 | -28 | 75W | 246 | 77W | ||
| 4 | BXO – 6 | -34 | 63W | 234 | 65W | ~11 | |
| 5 | CAO – 7 | -20 | 25E | 146 | 23E | 7.5 | |
| 6 | CSO – 4 | -16 | 67E | 104 | 65E | ~9 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.