Daily Sunspot Evaluation
Observation Sheet Thursday, 13 April 1972
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)
- 6
- Number of spots (f)
- 41
- Relative number (R)
- 101
- Observer
- ED
- Reading
- all checks consistent
- File
- 19720413.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | J – 1 | 8 | 43E | 28 | |||
| 2 | D – 12 | -12 | 19E | 52 | |||
| 3 | D – 7 | -15 | 22W | 93 | |||
| 4 | E – 18 | -8 | 12W | 83 | |||
| 5 | A – 2 | 9 | 20W | 91 | |||
| 6 | A – 1 | 2 | 03W | 74 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.