Daily Sunspot Evaluation
Observation Sheet Wednesday, 18 June 1952
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)
- 20
- Relative number (R)
- 60
- Observer
- ET
- Reading
- all checks consistent
- File
- 19520618.jpg
Sunspot groups
| No | Group (class – spots) | r | p | Margin no. |
|---|---|---|---|---|
| 1 | J – 3 | 0.74 | 111 | |
| 2 | D – 7 | 0.34 | 171 | |
| 3 | J – 4 | 0.85 | 255 | |
| 4 | D – 6 | 0.26 | 357 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.