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: 04-13 (93), 04-14 (93), 04-28 (93), 04-29 (93), 04-30 (93) — by astronomy; check the weather when the night is within four days.

2032-04-13astronomy score per night — click a bar for that night2032-05-12

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2032-04-13 Tue	93	—	unknown	21:40–04:15 (good, 6.58 h)	50.2° 00:20	7.38	16%	113.5°
2032-04-14 Wed	93	—	unknown	21:45–04:10 (good, 6.42 h)	50.2° 00:15	7.32	25%	101.0°
2032-04-15 Thu	92	—	unknown	21:45–04:05 (good, 6.33 h)	50.2° 00:15	7.26	34%	88.7°
2032-04-16 Fri	89	—	unknown	21:45–04:00 (good, 6.25 h)	50.2° 00:10	7.2	43%	76.8°
2032-04-17 Sat	85	—	unknown	21:50–04:00 (good, 6.17 h)	50.2° 00:05	7.15	53%	65.0°
2032-04-18 Sun	81	—	unknown	22:45–03:55 (good, 5.17 h)	50.2° 00:00	7.09	62%	53.3°
2032-04-19 Mon	60	—	unknown	03:40–03:50 (good, 0.17 h)	50.2° 00:00	7.03	71%	41.6°
2032-04-20 Tue	37	—	unknown	21:55–04:15 (marginal, 6.33 h)	50.2° 23:55	6.97	79%	30.0°
2032-04-21 Wed	29	—	unknown	21:55–03:55 (marginal, 6.0 h)	50.2° 23:50	6.91	86%	18.7°
2032-04-22 Thu	23	—	unknown	21:55–03:45 (marginal, 5.83 h)	50.2° 23:45	6.86	92%	9.1°
2032-04-23 Fri	20	—	unknown	22:00–03:30 (marginal, 5.5 h)	50.2° 23:40	6.8	97%	10.9°
2032-04-24 Sat	21	—	unknown	22:00–03:15 (marginal, 5.25 h)	50.2° 23:40	6.74	100%	21.8°
2032-04-25 Sun	27	—	unknown	22:00–03:10 (marginal, 5.17 h)	50.2° 23:35	6.68	100%	34.3°
2032-04-26 Mon	42	—	unknown	22:00–03:25 (marginal, 5.42 h)	50.2° 23:30	6.62	98%	47.3°
2032-04-27 Tue	83	—	unknown	22:05–00:20 (good, 2.25 h)	50.2° 23:25	6.56	94%	60.6°
2032-04-28 Wed	93	—	unknown	22:05–02:05 (good, 4.0 h)	50.2° 23:20	6.51	88%	74.2°
2032-04-29 Thu	93	—	unknown	22:05–02:50 (good, 4.75 h)	50.2° 23:20	6.45	79%	87.9°
2032-04-30 Fri	93	—	unknown	22:10–02:55 (good, 4.75 h)	50.2° 23:15	6.39	69%	101.8°
2032-05-01 Sat	93	—	unknown	22:10–02:55 (good, 4.75 h)	50.2° 23:10	6.33	58%	115.7°
2032-05-02 Sun	93	—	unknown	22:10–02:55 (good, 4.75 h)	50.2° 23:05	6.27	47%	129.7°
2032-05-03 Mon	93	—	unknown	22:15–02:55 (good, 4.67 h)	50.2° 23:05	6.22	36%	143.6°
2032-05-04 Tue	93	—	unknown	22:15–02:50 (good, 4.58 h)	50.2° 23:00	6.16	25%	157.2°
2032-05-05 Wed	93	—	unknown	22:15–02:45 (good, 4.5 h)	50.2° 22:55	6.1	16%	169.4°
2032-05-06 Thu	93	—	unknown	22:20–02:45 (good, 4.42 h)	50.2° 22:50	6.04	8%	169.8°
2032-05-07 Fri	93	—	unknown	22:20–02:40 (good, 4.33 h)	50.2° 22:45	5.99	3%	157.9°
2032-05-08 Sat	93	—	unknown	22:20–02:35 (good, 4.25 h)	50.2° 22:45	5.93	0%	144.8°
2032-05-09 Sun	93	—	unknown	22:25–02:30 (good, 4.08 h)	50.2° 22:40	5.88	0%	131.5°
2032-05-10 Mon	93	—	unknown	22:25–02:25 (good, 4.0 h)	50.2° 22:35	5.82	2%	118.5°
2032-05-11 Tue	93	—	unknown	22:25–02:25 (good, 4.0 h)	50.2° 22:30	5.76	6%	105.7°
2032-05-12 Wed	91	—	unknown	22:30–02:20 (good, 3.83 h)	50.2° 22:25	5.71	12%	93.2°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2032-04-13&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.