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: 12-27 (85), 12-28 (85), 12-26 (84), 12-29 (84), 12-25 (82) — by astronomy; check the weather when the night is within four days.

2036-11-30astronomy score per night — click a bar for that night2036-12-29

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-11-30 Sun	36	—	unknown	04:30–05:50 (good, 1.33 h)	50.2° 08:10	11.32	92%	150.2°
2036-12-01 Mon	37	—	unknown	04:30–05:55 (good, 1.42 h)	50.2° 08:05	11.34	96%	137.0°
2036-12-02 Tue	34	—	unknown	04:25–05:55 (good, 1.5 h)	50.2° 08:00	11.36	99%	123.4°
2036-12-03 Wed	30	—	unknown	04:30–05:55 (good, 1.42 h)	50.2° 07:55	11.37	100%	109.4°
2036-12-04 Thu	24	—	unknown	05:00–05:55 (good, 0.92 h)	50.2° 07:55	11.39	98%	95.2°
2036-12-05 Fri	19	—	unknown	03:45–05:55 (marginal, 2.17 h)	50.2° 07:50	11.4	93%	80.9°
2036-12-06 Sat	16	—	unknown	03:50–05:55 (marginal, 2.08 h)	50.2° 07:45	11.41	86%	66.4°
2036-12-07 Sun	15	—	unknown	03:50–06:00 (marginal, 2.17 h)	50.2° 07:40	11.43	77%	52.0°
2036-12-08 Mon	15	—	unknown	03:45–06:00 (marginal, 2.25 h)	50.2° 07:40	11.44	66%	37.7°
2036-12-09 Tue	19	—	unknown	03:30–06:00 (marginal, 2.5 h)	50.2° 07:35	11.45	55%	23.5°
2036-12-10 Wed	27	—	unknown	05:00–06:00 (good, 1.0 h)	50.2° 07:30	11.46	44%	9.5°
2036-12-11 Thu	36	—	unknown	04:00–06:00 (good, 2.0 h)	50.2° 07:25	11.47	33%	4.4°
2036-12-12 Fri	44	—	unknown	03:45–06:00 (good, 2.25 h)	50.2° 07:20	11.48	23%	18.1°
2036-12-13 Sat	53	—	unknown	03:30–06:05 (good, 2.58 h)	50.2° 07:20	11.48	15%	31.6°
2036-12-14 Sun	59	—	unknown	03:25–06:05 (good, 2.67 h)	50.2° 07:15	11.49	8%	44.9°
2036-12-15 Mon	65	—	unknown	03:25–06:05 (good, 2.67 h)	50.2° 07:10	11.49	3%	58.1°
2036-12-16 Tue	66	—	unknown	03:20–06:05 (good, 2.75 h)	50.2° 07:05	11.5	1%	71.0°
2036-12-17 Wed	68	—	unknown	03:15–06:05 (good, 2.83 h)	50.2° 07:00	11.5	0%	83.7°
2036-12-18 Thu	69	—	unknown	03:10–06:05 (good, 2.92 h)	50.2° 07:00	11.5	2%	96.2°
2036-12-19 Fri	71	—	unknown	03:10–06:05 (good, 2.92 h)	50.2° 06:55	11.51	5%	108.4°
2036-12-20 Sat	73	—	unknown	03:05–06:05 (good, 3.0 h)	50.2° 06:50	11.51	10%	120.5°
2036-12-21 Sun	74	—	unknown	03:00–06:05 (good, 3.08 h)	50.2° 06:45	11.51	16%	132.5°
2036-12-22 Mon	76	—	unknown	02:55–06:10 (good, 3.25 h)	50.2° 06:45	11.51	24%	144.3°
2036-12-23 Tue	78	—	unknown	02:50–06:10 (good, 3.33 h)	50.2° 06:40	11.5	32%	156.2°
2036-12-24 Wed	80	—	unknown	02:50–06:10 (good, 3.33 h)	50.2° 06:35	11.5	42%	168.0°
2036-12-25 Thu	82	—	unknown	02:45–06:10 (good, 3.42 h)	50.2° 06:30	11.5	51%	179.6°
2036-12-26 Fri	84	—	unknown	02:40–06:10 (good, 3.5 h)	50.2° 06:25	11.49	61%	167.8°
2036-12-27 Sat	85	—	unknown	02:35–06:10 (good, 3.58 h)	50.2° 06:25	11.49	70%	155.3°
2036-12-28 Sun	85	—	unknown	02:40–06:10 (good, 3.5 h)	50.2° 06:20	11.48	79%	142.4°
2036-12-29 Mon	84	—	unknown	02:35–06:10 (good, 3.58 h)	50.2° 06:15	11.47	87%	129.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-11-30&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.