Daily Sunspot Evaluation
Observation Sheet Sunday, 13 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)
- 2
- Number of spots (f)
- 7
- Relative number (R)
- 27
- Observer
- HG
- Reading
- all checks consistent
- File
- 19870913.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | ? – 1 | -23 | 74W | 338 | 76W | -72 | 64 |
| 2 | HAX – 6 | -33 | 34E | 230 | 32E | 4 | 67 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.