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: 01-15 (91), 12-30 (89), 12-29 (88), 12-31 (88), 01-01 (87) — by astronomy; check the weather when the night is within four days.

2033-12-17astronomy score per night — click a bar for that night2034-01-15

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
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°
2033-12-19 Mon	71	—	unknown	03:10–06:05 (good, 2.92 h)	50.2° 06:55	11.51	4%	60.8°
2033-12-20 Tue	72	—	unknown	03:05–06:05 (good, 3.0 h)	50.2° 06:50	11.51	1%	73.2°
2033-12-21 Wed	73	—	unknown	03:00–06:05 (good, 3.08 h)	50.2° 06:50	11.51	0%	85.8°
2033-12-22 Thu	76	—	unknown	02:55–06:10 (good, 3.25 h)	50.2° 06:45	11.51	2%	98.7°
2033-12-23 Fri	78	—	unknown	02:55–06:10 (good, 3.25 h)	50.2° 06:40	11.5	5%	111.8°
2033-12-24 Sat	79	—	unknown	02:50–06:10 (good, 3.33 h)	50.2° 06:35	11.5	11%	125.0°
2033-12-25 Sun	82	—	unknown	02:45–06:10 (good, 3.42 h)	50.2° 06:30	11.5	18%	138.4°
2033-12-26 Mon	83	—	unknown	02:40–06:10 (good, 3.5 h)	50.2° 06:30	11.49	28%	151.9°
2033-12-27 Tue	84	—	unknown	02:35–06:10 (good, 3.58 h)	50.2° 06:25	11.49	38%	165.3°
2033-12-28 Wed	86	—	unknown	02:35–06:10 (good, 3.58 h)	50.2° 06:20	11.48	49%	175.1°
2033-12-29 Thu	88	—	unknown	02:30–06:10 (good, 3.67 h)	50.2° 06:15	11.48	60%	164.9°
2033-12-30 Fri	89	—	unknown	02:30–06:10 (good, 3.67 h)	50.2° 06:10	11.47	71%	151.1°
2033-12-31 Sat	88	—	unknown	02:30–06:10 (good, 3.67 h)	50.2° 06:10	11.46	81%	136.9°
2034-01-01 Sun	87	—	unknown	02:25–06:10 (good, 3.75 h)	50.2° 06:05	11.45	89%	122.7°
2034-01-02 Mon	81	—	unknown	02:35–06:10 (good, 3.58 h)	50.2° 06:00	11.44	95%	108.4°
2034-01-03 Tue	58	—	unknown	03:10–06:10 (good, 3.0 h)	50.2° 05:55	11.43	99%	94.3°
2034-01-04 Wed	45	—	unknown	04:40–06:10 (good, 1.5 h)	50.2° 05:55	11.41	100%	80.3°
2034-01-05 Thu	33	—	unknown	02:00–06:10 (marginal, 4.17 h)	50.2° 05:50	11.4	98%	66.7°
2034-01-06 Fri	25	—	unknown	02:10–06:10 (marginal, 4.0 h)	50.2° 05:45	11.39	95%	53.4°
2034-01-07 Sat	20	—	unknown	02:15–06:10 (marginal, 3.92 h)	50.2° 05:40	11.37	89%	40.5°
2034-01-08 Sun	19	—	unknown	02:05–06:10 (marginal, 4.08 h)	50.2° 05:35	11.36	82%	27.9°
2034-01-09 Mon	25	—	unknown	01:40–06:10 (marginal, 4.5 h)	50.2° 05:35	11.34	74%	15.9°
2034-01-10 Tue	33	—	unknown	01:25–06:10 (marginal, 4.75 h)	50.2° 05:30	11.32	65%	5.7°
2034-01-11 Wed	44	—	unknown	01:10–06:10 (marginal, 5.0 h)	50.2° 05:25	11.3	56%	10.1°
2034-01-12 Thu	57	—	unknown	02:00–06:10 (good, 4.17 h)	50.2° 05:20	11.29	46%	21.2°
2034-01-13 Fri	79	—	unknown	01:30–06:10 (good, 4.67 h)	50.2° 05:15	11.27	37%	32.9°
2034-01-14 Sat	87	—	unknown	01:25–06:10 (good, 4.75 h)	50.2° 05:15	11.24	28%	44.7°
2034-01-15 Sun	91	—	unknown	01:20–06:10 (good, 4.83 h)	50.2° 05:10	11.22	20%	56.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-12-17&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.