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: 12-08 (43), 12-09 (42), 12-10 (41), 12-11 (40), 12-06 (39) — by astronomy; check the weather when the night is within four days.

2033-11-30astronomy score per night — click a bar for that night2033-12-29

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-11-30 Wed	26	—	unknown	18:35–19:05 (good, 0.5 h)	71.1° 15:45	11.32	64%	58.6°
2033-12-01 Thu	25	—	unknown	18:35–18:55 (good, 0.33 h)	71.1° 15:40	11.34	75%	69.1°
2033-12-02 Fri	25	—	unknown	18:35–19:05 (good, 0.5 h)	71.1° 15:35	11.35	84%	80.3°
2033-12-03 Sat	28	—	unknown	18:35–19:40 (good, 1.08 h)	71.1° 15:30	11.37	92%	92.0°
2033-12-04 Sun	32	—	unknown	18:35–20:10 (good, 1.58 h)	71.1° 15:30	11.38	97%	103.7°
2033-12-05 Mon	37	—	unknown	18:35–20:15 (good, 1.67 h)	71.1° 15:25	11.4	100%	114.9°
2033-12-06 Tue	39	—	unknown	18:35–20:15 (good, 1.67 h)	71.1° 15:20	11.41	99%	125.2°
2033-12-07 Wed	39	—	unknown	18:35–20:15 (good, 1.67 h)	71.1° 15:15	11.42	96%	133.8°
2033-12-08 Thu	43	—	unknown	18:35–20:10 (good, 1.58 h)	71.1° 15:15	11.44	91%	139.8°
2033-12-09 Fri	42	—	unknown	18:35–20:15 (good, 1.67 h)	71.1° 15:10	11.45	84%	142.3°
2033-12-10 Sat	41	—	unknown	18:35–20:10 (good, 1.58 h)	71.1° 15:05	11.46	76%	140.8°
2033-12-11 Sun	40	—	unknown	18:35–20:05 (good, 1.5 h)	71.1° 15:00	11.47	66%	136.2°
2033-12-12 Mon	38	—	unknown	18:35–20:05 (good, 1.5 h)	71.1° 14:55	11.47	57%	129.5°
2033-12-13 Tue	36	—	unknown	18:35–20:00 (good, 1.42 h)	71.1° 14:55	11.48	47%	121.6°
2033-12-14 Wed	35	—	unknown	18:35–19:55 (good, 1.33 h)	71.1° 14:50	11.49	38%	113.0°
2033-12-15 Thu	34	—	unknown	18:35–19:50 (good, 1.25 h)	71.1° 14:45	11.49	29%	103.9°
2033-12-16 Fri	32	—	unknown	18:35–19:50 (good, 1.25 h)	71.1° 14:40	11.5	21%	94.7°
2033-12-17 Sat	31	—	unknown	18:35–19:45 (good, 1.17 h)	71.1° 14:35	11.5	14%	85.2°
2033-12-18 Sun	29	—	unknown	18:35–19:40 (good, 1.08 h)	71.1° 14:35	11.5	8%	75.8°
2033-12-19 Mon	28	—	unknown	18:35–19:35 (good, 1.0 h)	71.1° 14:30	11.51	4%	66.5°
2033-12-20 Tue	27	—	unknown	18:35–19:30 (good, 0.92 h)	71.1° 14:25	11.51	1%	57.6°
2033-12-21 Wed	25	—	unknown	18:35–19:30 (good, 0.92 h)	71.1° 14:20	11.51	0%	49.4°
2033-12-22 Thu	23	—	unknown	18:35–19:25 (good, 0.83 h)	71.1° 14:20	11.51	2%	42.8°
2033-12-23 Fri	20	—	unknown	18:40–19:20 (good, 0.67 h)	71.1° 14:15	11.5	5%	38.6°
2033-12-24 Sat	18	—	unknown	18:40–19:10 (good, 0.5 h)	71.1° 14:10	11.5	11%	38.1°
2033-12-25 Sun	16	—	unknown	18:40–19:05 (good, 0.42 h)	71.1° 14:05	11.5	18%	41.4°
2033-12-26 Mon	13	—	unknown	18:40–18:55 (good, 0.25 h)	71.1° 14:00	11.49	28%	47.9°
2033-12-27 Tue	10	—	unknown	18:40–18:45 (good, 0.08 h)	71.1° 14:00	11.49	38%	56.6°
2033-12-28 Wed	8	—	unknown	18:40–19:30 (marginal, 0.83 h)	71.1° 13:55	11.48	49%	66.6°
2033-12-29 Thu	7	—	unknown	18:40–19:25 (marginal, 0.75 h)	71.1° 13:50	11.48	60%	77.4°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-11-30&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.