Rozhen Observation Calendar

Which nights are best for a target over the coming weeks. The astronomy mark (darkness × altitude × Moon) is computed for every night; the weather and the overall mark exist only where Open-Meteo has a forecast (the next four days) or ERA5 history (past nights) — the rest is honestly blank.

Best nights for HD 189733: 08-24 (100), 08-25 (100), 08-26 (100), 08-27 (100), 08-28 (100) — by astronomy; check the weather when the night is within four days.

2032-08-21astronomy score per night — click a bar for that night2032-09-19

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2032-08-21 Sat	46	—	unknown	21:55–04:20 (marginal, 6.42 h)	71.1° 23:20	7.02	99%	48.2°
2032-08-22 Sun	61	—	unknown	21:55–23:05 (good, 1.17 h)	71.1° 23:15	7.08	95%	58.0°
2032-08-23 Mon	75	—	unknown	21:50–01:30 (good, 3.67 h)	71.1° 23:10	7.13	88%	69.0°
2032-08-24 Tue	100	—	unknown	21:50–02:50 (good, 5.0 h)	71.1° 23:10	7.19	80%	80.3°
2032-08-25 Wed	100	—	unknown	21:50–03:45 (good, 5.92 h)	71.1° 23:05	7.25	70%	91.4°
2032-08-26 Thu	100	—	unknown	21:45–03:55 (good, 6.17 h)	71.1° 23:00	7.3	59%	102.2°
2032-08-27 Fri	100	—	unknown	21:45–03:55 (good, 6.17 h)	71.1° 22:55	7.36	49%	112.3°
2032-08-28 Sat	100	—	unknown	21:40–03:55 (good, 6.25 h)	71.1° 22:55	7.42	39%	121.7°
2032-08-29 Sun	100	—	unknown	21:40–03:50 (good, 6.17 h)	71.1° 22:50	7.47	29%	129.9°
2032-08-30 Mon	100	—	unknown	21:40–03:50 (good, 6.17 h)	71.1° 22:45	7.53	21%	136.7°
2032-08-31 Tue	100	—	unknown	21:35–03:45 (good, 6.17 h)	71.1° 22:40	7.59	14%	141.2°
2032-09-01 Wed	100	—	unknown	21:35–03:45 (good, 6.17 h)	71.1° 22:35	7.64	8%	142.9°
2032-09-02 Thu	100	—	unknown	21:30–03:40 (good, 6.17 h)	71.1° 22:35	7.7	4%	141.4°
2032-09-03 Fri	100	—	unknown	21:30–03:35 (good, 6.08 h)	71.1° 22:30	7.75	1%	137.1°
2032-09-04 Sat	100	—	unknown	21:30–03:30 (good, 6.0 h)	71.1° 22:25	7.81	0%	130.7°
2032-09-05 Sun	100	—	unknown	21:25–03:30 (good, 6.08 h)	71.1° 22:20	7.86	1%	122.9°
2032-09-06 Mon	100	—	unknown	21:25–03:25 (good, 6.0 h)	71.1° 22:15	7.92	4%	114.2°
2032-09-07 Tue	100	—	unknown	21:20–03:20 (good, 6.0 h)	71.1° 22:15	7.97	8%	105.0°
2032-09-08 Wed	100	—	unknown	21:20–03:15 (good, 5.92 h)	71.1° 22:10	8.03	14%	95.3°
2032-09-09 Thu	100	—	unknown	21:20–03:10 (good, 5.83 h)	71.1° 22:05	8.08	22%	85.5°
2032-09-10 Fri	100	—	unknown	21:15–03:10 (good, 5.92 h)	71.1° 22:00	8.14	31%	75.5°
2032-09-11 Sat	100	—	unknown	21:15–03:05 (good, 5.83 h)	71.1° 22:00	8.19	41%	65.6°
2032-09-12 Sun	98	—	unknown	21:10–03:00 (good, 5.83 h)	71.1° 21:55	8.24	52%	56.0°
2032-09-13 Mon	91	—	unknown	21:10–02:55 (good, 5.75 h)	71.1° 21:50	8.3	62%	47.4°
2032-09-14 Tue	82	—	unknown	21:10–02:50 (good, 5.67 h)	71.1° 21:45	8.35	73%	40.6°
2032-09-15 Wed	45	—	unknown	21:05–03:10 (marginal, 6.08 h)	71.1° 21:40	8.4	83%	37.2°
2032-09-16 Thu	35	—	unknown	21:05–02:55 (marginal, 5.83 h)	71.1° 21:40	8.45	91%	38.5°
2032-09-17 Fri	34	—	unknown	21:05–02:40 (marginal, 5.58 h)	71.1° 21:35	8.51	97%	44.3°
2032-09-18 Sat	39	—	unknown	21:00–02:35 (marginal, 5.58 h)	71.1° 21:30	8.56	100%	53.3°
2032-09-19 Sun	50	—	unknown	21:00–21:50 (good, 0.83 h)	71.1° 21:25	8.61	100%	64.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2032-08-21&days=30"
curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&days=30&format=csv" -o m31-calendar.csv

One row per night: score_astronomy always, score_weather / score only where a forecast or history exists (null otherwise, with weather_source saying which), best window, dark hours, Moon illumination and separation, transit. 7–60 nights. Errors: 400 with invalid_date or target_unresolved. Results are cached for six hours; calculation version 2026-10-10.1.