Daily Sunspot Evaluation
Observation Sheet Saturday, 17 February 1990
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)
- 12
- Relative number (R)
- 82
- Observer
- HE
- Reading
- all checks consistent
- File
- 19900217.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | ? – 1 | 12 | 75W | 142 | 77W | 1 | 66 |
| 2 | HK – 4 | 21 | 42W | 109 | 44W | 4.5 | 68 |
| 3 | AX – 1 | 23 | 32E | 35 | 30E | - | 75 |
| 4 | AX – 2 | 14 | 34E | 33 | 32E | 1 | 73 |
| 5 | AR – 2 | 10 | 67E | 0 | 65E | 1 | 76 |
| 6 | AX – 1 | -14 | 26W | 93 | 28W | - | 71 |
| 7 | ? – 1 | -10 | 81E | 346 | 79E | 2 | 77 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.