Daily Sunspot Evaluation
Observation Sheet Thursday, 17 September 1998
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)
- 8
- Number of spots (f)
- 30
- Relative number (R)
- 110
- Observer
- HE
- Reading
- all checks consistent
- File
- 19980917.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | BXO – 3 | 27 | 51W | 151 | 54W | 7.5 | 204 209 |
| 2 | ? – 1 | 31 | 82E | 18 | 79E | 3 | 214 219 |
| 3 | ? – 1 | 19 | 87E | 13 | 84E | 5 | 215 216 |
| 4 | AX – 1 | -24 | 56W | 156 | 59W | - | 206 205 |
| 5 | DAO – 8 | -21 | 11E | 89 | 08E | 9.5 | 210 209 |
| 6 | BXO – 4 | -40 | 39E | 61 | 36E | 4 | 212 211 |
| 7 | CAO – 5 | -29 | 49E | 51 | 46E | 7.5 | 213 212 |
| 8 | BXI – 7 | -16 | 54E | 46 | 51E | 7 | 216 215 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.