Daily Sunspot Evaluation
Observation Sheet Tuesday, 17 September 1974
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)
- 30
- Relative number (R)
- 70
- Observer
- FA
- Reading
- all checks consistent
- File
- 19740917.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | B – 4 | 8 | 57E | 183 | |||
| 2 | J – 1 | -16 | 14W | 254 | |||
| 3 | C – 4 | -10 | 30W | 270 | |||
| 4 | H – 21 | 8 | 26W | 266 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.