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: 04-28 (93), 04-29 (93), 04-30 (93), 05-01 (93), 05-02 (93) — by astronomy; check the weather when the night is within four days.

2032-04-28astronomy score per night — click a bar for that night2032-05-27

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
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°
2032-05-13 Thu	86	—	unknown	22:30–02:15 (good, 3.75 h)	50.2° 22:25	5.66	19%	81.0°
2032-05-14 Fri	79	—	unknown	22:30–02:10 (good, 3.67 h)	50.2° 22:20	5.6	27%	69.0°
2032-05-15 Sat	69	—	unknown	22:35–02:05 (good, 3.5 h)	50.2° 22:15	5.55	36%	57.2°
2032-05-16 Sun	55	—	unknown	22:35–02:05 (good, 3.5 h)	50.2° 22:10	5.5	46%	45.5°
2032-05-17 Mon	40	—	unknown	22:35–01:30 (good, 2.92 h)	50.2° 22:10	5.44	55%	33.9°
2032-05-18 Tue	30	—	unknown	22:40–02:20 (marginal, 3.67 h)	50.2° 22:05	5.39	64%	22.5°
2032-05-19 Wed	23	—	unknown	22:40–02:10 (marginal, 3.5 h)	50.2° 22:00	5.34	73%	11.9°
2032-05-20 Thu	18	—	unknown	22:40–02:00 (marginal, 3.33 h)	50.2° 21:55	5.29	82%	8.3°
2032-05-21 Fri	14	—	unknown	22:45–01:45 (marginal, 3.0 h)	50.2° 21:50	5.24	89%	17.5°
2032-05-22 Sat	13	—	unknown	22:45–01:30 (marginal, 2.75 h)	50.2° 21:50	5.2	94%	29.7°
2032-05-23 Sun	17	—	unknown	22:45–01:35 (marginal, 2.83 h)	50.2° 21:45	5.15	98%	42.6°
2032-05-24 Mon	23	—	unknown	22:45–01:40 (marginal, 2.92 h)	50.2° 21:40	5.1	100%	56.0°
2032-05-25 Tue	30	—	unknown	22:50–23:15 (good, 0.42 h)	50.2° 21:35	5.06	99%	69.8°
2032-05-26 Wed	39	—	unknown	22:50–00:40 (good, 1.83 h)	50.2° 21:30	5.01	96%	83.8°
2032-05-27 Thu	55	—	unknown	22:50–01:00 (good, 2.17 h)	50.2° 21:30	4.97	90%	98.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2032-04-28&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.