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 Vega: 03-05 (83), 03-06 (83), 03-07 (83), 03-04 (82), 03-08 (81) — by astronomy; check the weather when the night is within four days.

2036-02-17astronomy score per night — click a bar for that night2036-03-17

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-02-17 Sun	37	—	unknown	03:40–05:45 (good, 2.08 h)	87.1° 09:10	10.18	60%	71.0°
2036-02-18 Mon	40	—	unknown	03:30–05:40 (good, 2.17 h)	87.1° 09:05	10.14	50%	65.9°
2036-02-19 Tue	46	—	unknown	03:20–05:40 (good, 2.33 h)	87.1° 09:00	10.1	41%	61.9°
2036-02-20 Wed	53	—	unknown	03:00–05:40 (good, 2.67 h)	87.1° 08:55	10.06	32%	59.3°
2036-02-21 Thu	58	—	unknown	03:00–05:35 (good, 2.58 h)	87.1° 08:50	10.02	23%	58.1°
2036-02-22 Fri	64	—	unknown	02:55–05:35 (good, 2.67 h)	87.1° 08:50	9.97	16%	58.4°
2036-02-23 Sat	69	—	unknown	02:50–05:35 (good, 2.75 h)	87.1° 08:45	9.93	10%	60.2°
2036-02-24 Sun	71	—	unknown	02:45–05:35 (good, 2.83 h)	87.1° 08:40	9.89	5%	63.3°
2036-02-25 Mon	72	—	unknown	02:40–05:30 (good, 2.83 h)	87.1° 08:35	9.84	2%	67.6°
2036-02-26 Tue	73	—	unknown	02:40–05:30 (good, 2.83 h)	87.1° 08:30	9.8	0%	72.9°
2036-02-27 Wed	75	—	unknown	02:35–05:30 (good, 2.92 h)	87.1° 08:30	9.76	0%	78.8°
2036-02-28 Thu	75	—	unknown	02:30–05:25 (good, 2.92 h)	87.1° 08:25	9.71	3%	85.2°
2036-02-29 Fri	77	—	unknown	02:25–05:25 (good, 3.0 h)	87.1° 08:20	9.67	7%	91.9°
2036-03-01 Sat	78	—	unknown	02:20–05:25 (good, 3.08 h)	87.1° 08:15	9.62	14%	98.6°
2036-03-02 Sun	79	—	unknown	02:20–05:20 (good, 3.0 h)	87.1° 08:15	9.57	22%	105.1°
2036-03-03 Mon	80	—	unknown	02:15–05:20 (good, 3.08 h)	87.1° 08:10	9.53	31%	111.1°
2036-03-04 Tue	82	—	unknown	02:10–05:20 (good, 3.17 h)	87.1° 08:05	9.48	42%	116.1°
2036-03-05 Wed	83	—	unknown	02:05–05:20 (good, 3.25 h)	87.1° 08:00	9.44	53%	119.8°
2036-03-06 Thu	83	—	unknown	02:10–05:15 (good, 3.08 h)	87.1° 07:55	9.39	64%	121.7°
2036-03-07 Fri	83	—	unknown	02:05–05:15 (good, 3.17 h)	87.1° 07:55	9.34	75%	121.5°
2036-03-08 Sat	81	—	unknown	02:05–05:15 (good, 3.17 h)	87.1° 07:50	9.29	84%	119.1°
2036-03-09 Sun	70	—	unknown	02:05–05:10 (good, 3.08 h)	87.1° 07:45	9.24	92%	114.7°
2036-03-10 Mon	64	—	unknown	02:10–05:10 (good, 3.0 h)	87.1° 07:40	9.2	97%	108.7°
2036-03-11 Tue	56	—	unknown	02:15–05:05 (good, 2.83 h)	87.1° 07:35	9.15	100%	101.8°
2036-03-12 Wed	50	—	unknown	02:50–05:05 (good, 2.25 h)	87.1° 07:35	9.1	100%	94.4°
2036-03-13 Thu	45	—	unknown	03:15–05:05 (good, 1.83 h)	87.1° 07:30	9.05	97%	86.9°
2036-03-14 Fri	42	—	unknown	03:30–05:00 (good, 1.5 h)	87.1° 07:25	9.0	92%	79.8°
2036-03-15 Sat	43	—	unknown	03:25–05:00 (good, 1.58 h)	87.1° 07:20	8.95	85%	73.3°
2036-03-16 Sun	45	—	unknown	02:50–05:00 (good, 2.17 h)	87.1° 07:20	8.9	77%	67.7°
2036-03-17 Mon	49	—	unknown	01:50–04:55 (good, 3.08 h)	87.1° 07:15	8.85	68%	63.2°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-02-17&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.