Daily Sunspot Evaluation
Observation Sheet Friday, 18 September 1987
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)
- 3
- Number of spots (f)
- 9
- Relative number (R)
- 39
- Observer
- HG
- Reading
- all checks consistent
- File
- 19870918.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | HAX – 1 | 13 | 68E | 131 | 66E | 2.578 | 68 |
| 2 | CAI – 6 | -32 | 29W | 228 | 31W | 6.76 | 67 |
| 3 | BXO – 2 | -30 | 07E | 192 | 05E | 2.79 | 69 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.