The two observing sites
Horizon profiles measured with Stellarium AR screenshots — eight per site, heights read off the alt/az gridlines, accurate to ±2–3°. Twelve metres apart, two different skies.
Site A
Decking by the back door · ///commented.target.menu · 51.580894, -0.020053
Decking by the back door. The house is right on top of you here — the southern sky is the casualty.
- N ~20° — palm and hedge
- NNE–NE ~22° — big hedge
- ENE (40–85°) ~10° — the most open direction
- E ~28° — gable
- SE ~48° — rooflines
- SSE (155–177°) ~28° — the “side-return slot”, the only usable southern view
- S–SSW (180–210°) ~48–50° — our own house wall
- SW ~40° falling to 22°
- WSW–W ~15° — garden wall
- WNW ~7–16° — rooftops and a tree
- NW ~19° — tower block
- W 265–288° — bridged between walls, not measured
Measured profile (48 points)
| Azimuth | Obstruction altitude |
|---|---|
| 0° | 20° |
| 5° | 21° |
| 10° | 22° |
| 15° | 23° |
| 20° | 23° |
| 25° | 20° |
| 30° | 15° |
| 35° | 9° |
| 42° | 17° |
| 50° | 12° |
| 60° | 10.5° |
| 70° | 9° |
| 78° | 10° |
| 85° | 20° |
| 90° | 28° |
| 100° | 38° |
| 110° | 42° |
| 120° | 47° |
| 130° | 48° |
| 140° | 45° |
| 150° | 40° |
| 157° | 30° |
| 165° | 28° |
| 175° | 32° |
| 180° | 48° |
| 190° | 49° |
| 200° | 49° |
| 210° | 45° |
| 220° | 40° |
| 228° | 22° |
| 235° | 16° |
| 245° | 15° |
| 255° | 15° |
| 265° | 15° |
| 275° | 15° |
| 285° | 14° |
| 292° | 14° |
| 300° | 16° |
| 305° | 15° |
| 310° | 7° |
| 318° | 7° |
| 325° | 19° |
| 330° | 19° |
| 336° | 18° |
| 342° | 14° |
| 350° | 10° |
| 355° | 11° |
| 360° | 20° |
Site B
Decking by the summer house, bottom of the garden · ///served.joke.entertainer · 51.581002, -0.020140
Decking by the summer house, twelve metres down the garden — and those twelve metres drop the southern obstruction from 48° to 11°.
- N ~17° — the summer house itself
- NE ~20°→12° — summer-house corner
- ENE ~11° — open
- E–ESE (90–118°) ~18–32° — a banana palm (prunable — the single best improvement available)
- SE (120–150°) ~19–20° — the main house
- S (165–200°) ~10–12° — neighbouring terrace; the southern sky is effectively open
- SW ~4–8° — very open
- W (255–290°) ~29° — a large tree
- WNW ~12° — rooftops
- NW ~20° — summer house
Measured profile (51 points)
| Azimuth | Obstruction altitude |
|---|---|
| 0° | 17° |
| 10° | 17° |
| 20° | 19° |
| 30° | 20° |
| 38° | 15° |
| 45° | 12° |
| 50° | 11° |
| 55° | 12° |
| 60° | 18° |
| 65° | 14° |
| 70° | 10° |
| 78° | 8° |
| 85° | 10° |
| 90° | 18° |
| 95° | 26° |
| 100° | 28° |
| 105° | 30° |
| 110° | 32° |
| 115° | 31° |
| 120° | 25° |
| 125° | 20° |
| 130° | 20° |
| 140° | 19° |
| 150° | 17° |
| 160° | 13° |
| 165° | 14° |
| 170° | 12° |
| 180° | 11° |
| 190° | 10° |
| 197° | 9° |
| 205° | 8° |
| 215° | 8° |
| 222° | 7° |
| 228° | 4° |
| 235° | 4° |
| 242° | 6° |
| 248° | 20° |
| 255° | 28° |
| 265° | 30° |
| 275° | 29° |
| 285° | 26° |
| 291° | 13° |
| 296° | 28° |
| 302° | 12° |
| 310° | 11° |
| 316° | 14° |
| 322° | 20° |
| 330° | 20° |
| 340° | 18° |
| 350° | 17° |
| 360° | 17° |