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: 05-28 (57), 05-29 (57), 05-30 (56), 05-31 (56), 05-27 (55) — by astronomy; check the weather when the night is within four days.

2032-05-22astronomy score per night — click a bar for that night2032-06-20

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
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°
2032-05-28 Fri	57	—	unknown	22:55–01:05 (good, 2.17 h)	50.2° 21:25	4.93	82%	112.3°
2032-05-29 Sat	57	—	unknown	22:55–01:05 (good, 2.17 h)	50.2° 21:20	4.89	72%	126.5°
2032-05-30 Sun	56	—	unknown	22:55–01:10 (good, 2.25 h)	50.2° 21:15	4.85	61%	140.5°
2032-05-31 Mon	56	—	unknown	22:55–01:05 (good, 2.17 h)	50.2° 21:15	4.81	49%	154.2°
2032-06-01 Tue	52	—	unknown	23:00–01:00 (good, 2.0 h)	50.2° 21:10	4.78	38%	166.9°
2032-06-02 Wed	51	—	unknown	23:00–00:55 (good, 1.92 h)	50.2° 21:05	4.74	28%	171.7°
2032-06-03 Thu	49	—	unknown	23:00–00:55 (good, 1.92 h)	50.2° 21:00	4.71	18%	161.4°
2032-06-04 Fri	47	—	unknown	23:00–00:50 (good, 1.83 h)	50.2° 20:55	4.68	11%	148.6°
2032-06-05 Sat	45	—	unknown	23:05–00:45 (good, 1.67 h)	50.2° 20:55	4.65	5%	135.6°
2032-06-06 Sun	43	—	unknown	23:05–00:40 (good, 1.58 h)	50.2° 20:50	4.62	1%	122.7°
2032-06-07 Mon	41	—	unknown	23:05–00:35 (good, 1.5 h)	50.2° 20:45	4.59	0%	109.9°
2032-06-08 Tue	40	—	unknown	23:05–00:35 (good, 1.5 h)	50.2° 20:40	4.57	1%	97.4°
2032-06-09 Wed	38	—	unknown	23:05–00:30 (good, 1.42 h)	50.2° 20:35	4.54	4%	85.1°
2032-06-10 Thu	37	—	unknown	23:05–00:25 (good, 1.33 h)	50.2° 20:35	4.52	8%	72.9°
2032-06-11 Fri	34	—	unknown	23:10–00:20 (good, 1.17 h)	50.2° 20:30	4.5	14%	61.0°
2032-06-12 Sat	30	—	unknown	23:10–00:15 (good, 1.08 h)	50.2° 20:25	4.49	22%	49.3°
2032-06-13 Sun	24	—	unknown	23:10–00:00 (good, 0.83 h)	50.2° 20:20	4.47	30%	37.6°
2032-06-14 Mon	20	—	unknown	23:10–23:50 (good, 0.67 h)	50.2° 20:20	4.46	39%	26.2°
2032-06-15 Tue	16	—	unknown	23:10–23:35 (good, 0.42 h)	50.2° 20:15	4.45	48%	15.2°
2032-06-16 Wed	13	—	unknown	23:10–00:30 (marginal, 1.33 h)	50.2° 20:10	4.44	58%	7.6°
2032-06-17 Thu	10	—	unknown	23:10–00:15 (marginal, 1.08 h)	50.2° 20:05	4.43	67%	13.5°
2032-06-18 Fri	7	—	unknown	23:10–00:05 (marginal, 0.92 h)	50.2° 20:00	4.43	76%	24.9°
2032-06-19 Sat	7	—	unknown	23:10–23:55 (marginal, 0.75 h)	50.2° 20:00	4.42	85%	37.5°
2032-06-20 Sun	7	—	unknown	23:15–23:55 (marginal, 0.67 h)	50.2° 19:55	4.42	92%	50.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2032-05-22&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.