Daily Sunspot Evaluation
Observation Sheet Saturday, 17 August 1991
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)
- 19
- Number of spots (f)
- 215
- Relative number (R)
- 405
- Observer
- HÇ0
- Reading
- all checks consistent
- File
- 19910817.jpg
Sunspot groups
| No | Group (class – spots) | B | Δ L | L | Δ Lf | U | Margin no. |
|---|---|---|---|---|---|---|---|
| 1 | CAO – 6 | 24 | 09E | 50 | 06E | 4.5 | 436 |
| 2 | AX – 3 | 8 | 19E | 40 | 16E | - | 443 |
| 3 | BXI – 3 | 9 | 55E | 4 | 52E | 4 | 453 |
| 4 | CAO – 4 | 10 | 63E | 356 | 60E | 6 | 444 |
| 5 | CAI – 8 | 2 | 67E | 351 | 64E | 8.5 | 443 |
| 6 | HA – 1 | 2 | 78E | 341 | 75E | 2 | 434 |
| 7 | ? – 2 | 10 | 85E | 334 | 82E | 4 | 455 |
| 8 | AX – 1 | -12 | 71W | 130 | 74W | - | 429 |
| 9 | HS – 1 | -25 | 55W | 114 | 58W | 2 | 431 |
| 10 | HA – 3 | -8 | 11E | 48 | 08E | 3.5 | 438 |
| 11 | CAI – 58 | -19 | 16E | 43 | 13E | 12.5 | 435 |
| 12 | DAC – 56 | -17 | 31E | 28 | 28E | 7.5 | 440 |
| 13 | DKO – 17 | -10 | 32E | 27 | 29E | 8 | 441 |
| 14 | AX – 2 | -7 | 34E | 25 | 31E | 1 | 446 |
| 15 | EKC – 35 | -10 | 47E | 12 | 44E | 13 | 444 |
| 16 | HA – 3 | -4 | 56E | 3 | 53E | 2 | 448 |
| 17 | AX – 2 | -14 | 58E | 1 | 55E | 1.5 | 450 |
| 18 | HA – 2 | -26 | 60E | 359 | 57E | 2.5 | 451 |
| 19 | CAI – 8 | -17 | 64E | 355 | 61E | 11 | 452 |
Class as written on the sheet (? = group the observer marked as uncertain). ⚠: the coordinates of this row do not agree with each other.