Daily Sunspot Evaluation
Observation Sheet Thursday, 21 May 1987
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)
- 2
- Number of spots (f)
- 30
- Relative number (R)
- 50
- Observer
- HM
- Reading
- all checks consistent
- File
- 19870521.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | EKC – 28 | 30 | 09E | 340 | 04E | 14.5 | 9 |
| 2 | AXX – 2 | -25 | 00 | 347 | 03E | - | 32 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.