Daily Sunspot Evaluation
Observation Sheet Tuesday, 20 September 1977
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)
- 4
- Number of spots (f)
- 50
- Relative number (R)
- 90
- Observer
- GA
- Reading
- all checks consistent
- File
- 19770920.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | ? – 1 | 25 | 20E | 115 | 19E | ||
| 2 | H – 31 | -23 | 39E | 98 | 34E | ||
| 3 | A – 1 | 1 | 05W | 140 | 08W | ||
| 4 | H – 17 | 9 | 65W | 200 | 68W |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.