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: 04-06 (52), 04-08 (51), 04-04 (50), 04-05 (50), 04-07 (50) — by astronomy; check the weather when the night is within four days.

2033-03-10astronomy score per night — click a bar for that night2033-04-08

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-03-10 Thu	28	—	unknown	04:05–05:10 (good, 1.08 h)	71.1° 09:05	9.21	78%	140.9°
2033-03-11 Fri	29	—	unknown	04:05–05:10 (good, 1.08 h)	71.1° 09:00	9.16	85%	142.8°
2033-03-12 Sat	28	—	unknown	04:05–05:05 (good, 1.0 h)	71.1° 09:00	9.11	91%	141.5°
2033-03-13 Sun	26	—	unknown	04:00–05:05 (good, 1.08 h)	71.1° 08:55	9.06	96%	137.2°
2033-03-14 Mon	27	—	unknown	04:00–05:05 (good, 1.08 h)	71.1° 08:50	9.01	99%	130.9°
2033-03-15 Tue	26	—	unknown	03:55–05:00 (good, 1.08 h)	71.1° 08:45	8.96	100%	123.2°
2033-03-16 Wed	25	—	unknown	03:55–05:00 (good, 1.08 h)	71.1° 08:45	8.91	99%	114.6°
2033-03-17 Thu	22	—	unknown	03:55–04:55 (good, 1.0 h)	71.1° 08:40	8.86	97%	105.5°
2033-03-18 Fri	21	—	unknown	04:00–04:55 (good, 0.92 h)	71.1° 08:35	8.81	93%	96.1°
2033-03-19 Sat	20	—	unknown	04:10–04:55 (good, 0.75 h)	71.1° 08:30	8.76	87%	86.5°
2033-03-20 Sun	19	—	unknown	04:20–04:50 (good, 0.5 h)	71.1° 08:25	8.71	80%	76.9°
2033-03-21 Mon	19	—	unknown	04:20–04:50 (good, 0.5 h)	71.1° 08:25	8.65	71%	67.3°
2033-03-22 Tue	21	—	unknown	03:55–04:50 (good, 0.92 h)	71.1° 08:20	8.6	62%	58.1°
2033-03-23 Wed	23	—	unknown	03:35–04:45 (good, 1.17 h)	71.1° 08:15	8.55	52%	49.6°
2033-03-24 Thu	26	—	unknown	03:25–04:45 (good, 1.33 h)	71.1° 08:10	8.5	41%	42.4°
2033-03-25 Fri	31	—	unknown	03:05–04:40 (good, 1.58 h)	71.1° 08:05	8.44	30%	37.9°
2033-03-26 Sat	37	—	unknown	04:00–05:40 (good, 1.67 h)	71.1° 09:05	8.39	20%	37.5°
2033-03-27 Sun	42	—	unknown	04:00–05:40 (good, 1.67 h)	71.1° 09:00	8.34	12%	41.6°
2033-03-28 Mon	43	—	unknown	03:55–05:35 (good, 1.67 h)	71.1° 08:55	8.28	5%	49.4°
2033-03-29 Tue	44	—	unknown	03:50–05:35 (good, 1.75 h)	71.1° 08:50	8.23	1%	59.5°
2033-03-30 Wed	45	—	unknown	03:45–05:35 (good, 1.83 h)	71.1° 08:50	8.18	0%	70.9°
2033-03-31 Thu	46	—	unknown	03:40–05:30 (good, 1.83 h)	71.1° 08:45	8.12	2%	82.7°
2033-04-01 Fri	47	—	unknown	03:40–05:30 (good, 1.83 h)	71.1° 08:40	8.07	7%	94.6°
2033-04-02 Sat	47	—	unknown	03:35–05:25 (good, 1.83 h)	71.1° 08:35	8.01	14%	106.0°
2033-04-03 Sun	48	—	unknown	03:30–05:25 (good, 1.92 h)	71.1° 08:30	7.96	23%	116.6°
2033-04-04 Mon	50	—	unknown	03:25–05:25 (good, 2.0 h)	71.1° 08:30	7.9	33%	126.1°
2033-04-05 Tue	50	—	unknown	03:25–05:20 (good, 1.92 h)	71.1° 08:25	7.84	43%	134.1°
2033-04-06 Wed	52	—	unknown	03:20–05:20 (good, 2.0 h)	71.1° 08:20	7.79	53%	139.9°
2033-04-07 Thu	50	—	unknown	03:20–05:15 (good, 1.92 h)	71.1° 08:15	7.73	63%	142.7°
2033-04-08 Fri	51	—	unknown	03:15–05:15 (good, 2.0 h)	71.1° 08:10	7.68	72%	142.2°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-03-10&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.