Daily Sunspot Evaluation
Observation Sheet Thursday, 28 February 1957
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)
- 7
- Number of spots (f)
- 31
- Relative number (R)
- 101
- Observer
- MH
- Reading
- all checks consistent
- File
- 19570228.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | C – 3 | 22 | 30E | ||||
| 2 | ? – 3 | -10 | 70E | ||||
| 3 | ? – 1 | -13 | 76E | ||||
| 4 | A – 1 | -17 | 42E | ||||
| 5 | D – 7 | 14 | 41W | ||||
| 6 | A – 2 | 18 | 21W | ||||
| 7 | E – 14 | 33 | 1W |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.