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 3C 273: 12-18 (66), 12-17 (60), 12-16 (53), 12-15 (44), 12-02 (41) — by astronomy; check the weather when the night is within four days.

2033-11-19astronomy score per night — click a bar for that night2033-12-18

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-11-19 Sat	18	—	unknown	05:05–05:40 (good, 0.58 h)	50.2° 08:55	11.08	4%	28.5°
2033-11-20 Sun	21	—	unknown	05:05–05:45 (good, 0.67 h)	50.2° 08:50	11.1	1%	40.3°
2033-11-21 Mon	22	—	unknown	05:00–05:45 (good, 0.75 h)	50.2° 08:45	11.13	0%	52.2°
2033-11-22 Tue	24	—	unknown	04:55–05:45 (good, 0.83 h)	50.2° 08:40	11.15	1%	64.4°
2033-11-23 Wed	25	—	unknown	04:50–05:45 (good, 0.92 h)	50.2° 08:40	11.17	4%	76.7°
2033-11-24 Thu	27	—	unknown	04:45–05:45 (good, 1.0 h)	50.2° 08:35	11.2	8%	89.2°
2033-11-25 Fri	28	—	unknown	04:45–05:45 (good, 1.0 h)	50.2° 08:30	11.22	14%	101.9°
2033-11-26 Sat	30	—	unknown	04:40–05:50 (good, 1.17 h)	50.2° 08:25	11.24	22%	114.8°
2033-11-27 Sun	32	—	unknown	04:35–05:50 (good, 1.25 h)	50.2° 08:20	11.26	32%	127.9°
2033-11-28 Mon	33	—	unknown	04:30–05:50 (good, 1.33 h)	50.2° 08:20	11.28	42%	141.2°
2033-11-29 Tue	35	—	unknown	04:25–05:50 (good, 1.42 h)	50.2° 08:15	11.3	53%	154.8°
2033-11-30 Wed	37	—	unknown	04:25–05:50 (good, 1.42 h)	50.2° 08:10	11.32	64%	168.1°
2033-12-01 Thu	39	—	unknown	04:20–05:55 (good, 1.58 h)	50.2° 08:05	11.34	75%	173.7°
2033-12-02 Fri	41	—	unknown	04:15–05:55 (good, 1.67 h)	50.2° 08:00	11.35	84%	161.1°
2033-12-03 Sat	41	—	unknown	04:20–05:55 (good, 1.58 h)	50.2° 08:00	11.37	92%	146.6°
2033-12-04 Sun	37	—	unknown	04:20–05:55 (good, 1.58 h)	50.2° 07:55	11.38	97%	131.9°
2033-12-05 Mon	36	—	unknown	04:15–05:55 (good, 1.67 h)	50.2° 07:50	11.4	100%	117.3°
2033-12-06 Tue	30	—	unknown	04:25–05:55 (good, 1.5 h)	50.2° 07:45	11.41	99%	102.7°
2033-12-07 Wed	24	—	unknown	05:25–06:00 (good, 0.58 h)	50.2° 07:45	11.42	96%	88.5°
2033-12-08 Thu	20	—	unknown	03:40–06:00 (marginal, 2.33 h)	50.2° 07:40	11.44	91%	74.7°
2033-12-09 Fri	17	—	unknown	03:40–06:00 (marginal, 2.33 h)	50.2° 07:35	11.45	84%	61.2°
2033-12-10 Sat	16	—	unknown	03:40–06:00 (marginal, 2.33 h)	50.2° 07:30	11.46	76%	48.3°
2033-12-11 Sun	17	—	unknown	03:30–06:00 (marginal, 2.5 h)	50.2° 07:25	11.47	66%	35.7°
2033-12-12 Mon	21	—	unknown	03:20–06:00 (marginal, 2.67 h)	50.2° 07:25	11.47	57%	23.6°
2033-12-13 Tue	28	—	unknown	05:30–06:05 (good, 0.58 h)	50.2° 07:20	11.48	47%	12.1°
2033-12-14 Wed	36	—	unknown	03:50–06:05 (good, 2.25 h)	50.2° 07:15	11.49	38%	5.1°
2033-12-15 Thu	44	—	unknown	03:40–06:05 (good, 2.42 h)	50.2° 07:10	11.49	29%	13.6°
2033-12-16 Fri	53	—	unknown	03:30–06:05 (good, 2.58 h)	50.2° 07:05	11.5	21%	25.0°
2033-12-17 Sat	60	—	unknown	03:15–06:05 (good, 2.83 h)	50.2° 07:05	11.5	14%	36.7°
2033-12-18 Sun	66	—	unknown	03:15–06:05 (good, 2.83 h)	50.2° 07:00	11.5	8%	48.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-11-19&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.