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 V1057 Cyg: 05-24 (100), 05-25 (100), 05-26 (100), 05-27 (100), 05-28 (100) — by astronomy; check the weather when the night is within four days.

2033-05-22astronomy score per night — click a bar for that night2033-06-20

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-05-22 Sun	94	—	unknown	00:00–03:55 (good, 3.92 h)	87.3° 06:15	5.21	37%	54.9°
2033-05-23 Mon	98	—	unknown	00:00–03:55 (good, 3.92 h)	87.3° 06:15	5.16	26%	58.5°
2033-05-24 Tue	100	—	unknown	23:55–03:55 (good, 4.0 h)	87.3° 06:10	5.11	16%	64.1°
2033-05-25 Wed	100	—	unknown	23:50–03:55 (good, 4.08 h)	87.3° 06:05	5.07	9%	71.1°
2033-05-26 Thu	100	—	unknown	23:45–03:50 (good, 4.08 h)	87.3° 06:00	5.02	3%	79.1°
2033-05-27 Fri	100	—	unknown	23:40–03:50 (good, 4.17 h)	87.3° 05:55	4.98	0%	87.5°
2033-05-28 Sat	100	—	unknown	23:40–03:50 (good, 4.17 h)	87.3° 05:55	4.94	0%	95.8°
2033-05-29 Sun	100	—	unknown	23:35–03:50 (good, 4.25 h)	87.3° 05:50	4.9	3%	103.8°
2033-05-30 Mon	100	—	unknown	23:30–03:45 (good, 4.25 h)	87.3° 05:45	4.86	8%	110.9°
2033-05-31 Tue	100	—	unknown	23:25–03:45 (good, 4.33 h)	87.3° 05:40	4.82	14%	117.0°
2033-06-01 Wed	100	—	unknown	23:25–03:45 (good, 4.33 h)	87.3° 05:40	4.79	22%	121.7°
2033-06-02 Thu	100	—	unknown	23:20–03:45 (good, 4.42 h)	87.3° 05:35	4.75	31%	124.8°
2033-06-03 Fri	100	—	unknown	23:20–03:45 (good, 4.42 h)	87.3° 05:30	4.72	40%	126.0°
2033-06-04 Sat	100	—	unknown	23:15–03:45 (good, 4.5 h)	87.3° 05:25	4.68	50%	125.4°
2033-06-05 Sun	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 05:20	4.65	59%	123.1°
2033-06-06 Mon	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 05:20	4.63	68%	119.3°
2033-06-07 Tue	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 05:15	4.6	76%	114.3°
2033-06-08 Wed	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 05:10	4.57	84%	108.4°
2033-06-09 Thu	86	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 05:05	4.55	91%	101.7°
2033-06-10 Fri	78	—	unknown	23:20–03:40 (good, 4.33 h)	87.3° 05:00	4.53	96%	94.6°
2033-06-11 Sat	68	—	unknown	00:00–03:40 (good, 3.67 h)	87.3° 05:00	4.51	99%	87.1°
2033-06-12 Sun	59	—	unknown	00:40–03:40 (good, 3.0 h)	87.3° 04:55	4.49	100%	79.6°
2033-06-13 Mon	53	—	unknown	01:15–03:40 (good, 2.42 h)	87.3° 04:50	4.48	99%	72.3°
2033-06-14 Tue	50	—	unknown	01:30–03:40 (good, 2.17 h)	87.3° 04:45	4.46	95%	65.6°
2033-06-15 Wed	51	—	unknown	00:35–03:05 (good, 2.5 h)	87.3° 04:45	4.45	90%	60.0°
2033-06-16 Thu	75	—	unknown	23:10–03:40 (good, 4.5 h)	87.3° 04:40	4.44	82%	56.0°
2033-06-17 Fri	87	—	unknown	23:10–03:40 (good, 4.5 h)	87.3° 04:35	4.43	73%	54.1°
2033-06-18 Sat	93	—	unknown	23:10–03:40 (good, 4.5 h)	87.3° 04:30	4.43	62%	54.7°
2033-06-19 Sun	97	—	unknown	23:10–03:40 (good, 4.5 h)	87.3° 04:25	4.42	51%	57.6°
2033-06-20 Mon	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 04:25	4.42	39%	62.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-05-22&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.