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: 03-04 (93), 03-05 (93), 03-06 (93), 03-07 (93), 03-08 (93) — by astronomy; check the weather when the night is within four days.

2033-03-04astronomy score per night — click a bar for that night2033-04-02

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-03-04 Fri	93	—	unknown	22:15–05:20 (good, 7.08 h)	50.2° 02:00	9.49	18%	150.9°
2033-03-05 Sat	93	—	unknown	22:10–05:20 (good, 7.17 h)	50.2° 01:55	9.45	28%	136.9°
2033-03-06 Sun	93	—	unknown	22:10–05:15 (good, 7.08 h)	50.2° 01:50	9.4	38%	123.2°
2033-03-07 Mon	93	—	unknown	22:10–05:15 (good, 7.08 h)	50.2° 01:50	9.35	49%	109.9°
2033-03-08 Tue	93	—	unknown	22:15–05:15 (good, 7.0 h)	50.2° 01:45	9.31	59%	97.1°
2033-03-09 Wed	91	—	unknown	22:25–05:10 (good, 6.75 h)	50.2° 01:40	9.26	69%	84.5°
2033-03-10 Thu	87	—	unknown	23:50–05:10 (good, 5.33 h)	50.2° 01:35	9.21	78%	72.2°
2033-03-11 Fri	83	—	unknown	02:05–05:10 (good, 3.08 h)	50.2° 01:30	9.16	85%	60.1°
2033-03-12 Sat	66	—	unknown	05:00–05:05 (good, 0.08 h)	50.2° 01:30	9.11	91%	48.2°
2033-03-13 Sun	34	—	unknown	23:25–05:05 (marginal, 5.67 h)	50.2° 01:25	9.06	96%	36.4°
2033-03-14 Mon	26	—	unknown	01:20–05:05 (marginal, 3.75 h)	50.2° 01:20	9.01	99%	24.8°
2033-03-15 Tue	23	—	unknown	01:40–05:00 (marginal, 3.33 h)	50.2° 01:15	8.96	100%	13.7°
2033-03-16 Wed	23	—	unknown	21:40–05:00 (marginal, 7.33 h)	50.2° 01:10	8.91	99%	6.2°
2033-03-17 Thu	28	—	unknown	21:15–04:50 (marginal, 7.58 h)	50.2° 01:10	8.86	97%	13.0°
2033-03-18 Fri	40	—	unknown	20:50–04:50 (marginal, 8.0 h)	50.2° 01:05	8.81	93%	24.2°
2033-03-19 Sat	82	—	unknown	21:15–22:00 (good, 0.75 h)	50.2° 01:00	8.76	87%	35.9°
2033-03-20 Sun	88	—	unknown	21:10–01:10 (good, 4.0 h)	50.2° 00:55	8.71	80%	47.9°
2033-03-21 Mon	92	—	unknown	21:05–03:20 (good, 6.25 h)	50.2° 00:55	8.65	71%	60.2°
2033-03-22 Tue	93	—	unknown	21:00–04:15 (good, 7.25 h)	50.2° 00:50	8.6	62%	72.7°
2033-03-23 Wed	93	—	unknown	21:00–04:20 (good, 7.33 h)	50.2° 00:45	8.55	52%	85.6°
2033-03-24 Thu	93	—	unknown	20:55–04:25 (good, 7.5 h)	50.2° 00:40	8.5	41%	98.8°
2033-03-25 Fri	93	—	unknown	20:50–04:25 (good, 7.58 h)	50.2° 00:35	8.44	30%	112.5°
2033-03-26 Sat	93	—	unknown	20:45–05:25 (good, 7.67 h)	50.2° 00:35	8.39	20%	126.6°
2033-03-27 Sun	93	—	unknown	21:40–05:20 (good, 7.67 h)	50.2° 01:30	8.34	12%	141.0°
2033-03-28 Mon	93	—	unknown	21:40–05:15 (good, 7.58 h)	50.2° 01:25	8.28	5%	155.7°
2033-03-29 Tue	93	—	unknown	21:35–05:15 (good, 7.67 h)	50.2° 01:20	8.23	1%	169.6°
2033-03-30 Wed	93	—	unknown	21:30–05:10 (good, 7.67 h)	50.2° 01:15	8.18	0%	170.8°
2033-03-31 Thu	93	—	unknown	21:25–05:05 (good, 7.67 h)	50.2° 01:15	8.12	2%	157.2°
2033-04-01 Fri	93	—	unknown	21:25–05:00 (good, 7.58 h)	50.2° 01:10	8.07	7%	142.8°
2033-04-02 Sat	93	—	unknown	21:25–05:00 (good, 7.58 h)	50.2° 01:05	8.01	14%	128.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-03-04&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.