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: 03-06 (93), 03-07 (93), 03-08 (93), 03-09 (93), 03-10 (93) — by astronomy; check the weather when the night is within four days.

2043-03-06astronomy score per night — click a bar for that night2043-04-04

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-03-06 Fri	93	—	unknown	22:05–05:15 (good, 7.17 h)	50.1° 01:55	9.42	23%	103.8°
2043-03-07 Sat	93	—	unknown	22:05–05:15 (good, 7.17 h)	50.1° 01:50	9.37	15%	116.9°
2043-03-08 Sun	93	—	unknown	22:00–05:15 (good, 7.25 h)	50.1° 01:45	9.33	8%	130.3°
2043-03-09 Mon	93	—	unknown	21:55–05:10 (good, 7.25 h)	50.1° 01:40	9.28	3%	144.2°
2043-03-10 Tue	93	—	unknown	21:50–05:10 (good, 7.33 h)	50.1° 01:40	9.23	0%	158.3°
2043-03-11 Wed	93	—	unknown	21:50–05:10 (good, 7.33 h)	50.1° 01:35	9.18	0%	172.0°
2043-03-12 Thu	93	—	unknown	21:45–05:05 (good, 7.33 h)	50.1° 01:30	9.13	3%	170.7°
2043-03-13 Fri	93	—	unknown	21:40–05:05 (good, 7.42 h)	50.1° 01:25	9.08	9%	156.7°
2043-03-14 Sat	93	—	unknown	21:35–05:05 (good, 7.5 h)	50.1° 01:20	9.03	17%	142.1°
2043-03-15 Sun	93	—	unknown	21:35–05:00 (good, 7.42 h)	50.1° 01:20	8.98	27%	127.7°
2043-03-16 Mon	93	—	unknown	21:35–05:00 (good, 7.42 h)	50.1° 01:15	8.93	38%	113.5°
2043-03-17 Tue	92	—	unknown	21:35–05:00 (good, 7.42 h)	50.1° 01:10	8.88	49%	99.5°
2043-03-18 Wed	87	—	unknown	21:45–04:55 (good, 7.17 h)	50.1° 01:05	8.83	60%	85.9°
2043-03-19 Thu	82	—	unknown	23:00–04:55 (good, 5.92 h)	50.1° 01:05	8.78	70%	72.5°
2043-03-20 Fri	66	—	unknown	01:45–04:20 (good, 2.58 h)	50.1° 01:00	8.73	79%	59.4°
2043-03-21 Sat	47	—	unknown	21:20–04:50 (marginal, 7.5 h)	50.1° 00:55	8.68	87%	46.5°
2043-03-22 Sun	31	—	unknown	23:35–04:50 (marginal, 5.25 h)	50.1° 00:50	8.62	93%	33.9°
2043-03-23 Mon	24	—	unknown	01:15–04:45 (marginal, 3.5 h)	50.1° 00:45	8.57	97%	21.6°
2043-03-24 Tue	22	—	unknown	01:45–04:30 (marginal, 2.75 h)	50.1° 00:45	8.52	100%	9.8°
2043-03-25 Wed	22	—	unknown	21:05–04:20 (marginal, 7.25 h)	50.1° 00:40	8.47	100%	5.7°
2043-03-26 Thu	29	—	unknown	20:40–04:15 (marginal, 7.58 h)	50.1° 00:35	8.41	98%	16.1°
2043-03-27 Fri	53	—	unknown	20:45–20:50 (good, 0.08 h)	50.1° 00:30	8.36	95%	27.8°
2043-03-28 Sat	84	—	unknown	20:40–21:55 (good, 1.25 h)	50.1° 00:25	8.31	90%	39.5°
2043-03-29 Sun	90	—	unknown	21:35–02:15 (good, 4.67 h)	50.1° 01:25	8.25	84%	51.3°
2043-03-30 Mon	93	—	unknown	21:35–04:05 (good, 6.5 h)	50.1° 01:20	8.2	76%	63.1°
2043-03-31 Tue	93	—	unknown	21:30–04:45 (good, 7.25 h)	50.1° 01:15	8.14	68%	74.9°
2043-04-01 Wed	93	—	unknown	21:25–04:50 (good, 7.42 h)	50.1° 01:10	8.09	58%	87.0°
2043-04-02 Thu	93	—	unknown	21:25–04:50 (good, 7.42 h)	50.1° 01:10	8.03	49%	99.2°
2043-04-03 Fri	93	—	unknown	21:25–04:50 (good, 7.42 h)	50.1° 01:05	7.98	38%	111.8°
2043-04-04 Sat	93	—	unknown	21:30–04:50 (good, 7.33 h)	50.1° 01:00	7.92	29%	124.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-03-06&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.