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.

2033-05-10astronomy score per night — click a bar for that night2033-06-08

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-05-10 Tue	76	—	unknown	01:05–04:15 (good, 3.17 h)	87.3° 07:05	5.83	89%	118.0°
2033-05-11 Wed	72	—	unknown	01:05–04:15 (good, 3.17 h)	87.3° 07:00	5.78	94%	112.7°
2033-05-12 Thu	65	—	unknown	01:05–04:10 (good, 3.08 h)	87.3° 06:55	5.72	98%	106.4°
2033-05-13 Fri	60	—	unknown	01:10–04:10 (good, 3.0 h)	87.3° 06:50	5.67	100%	99.6°
2033-05-14 Sat	54	—	unknown	01:25–04:10 (good, 2.75 h)	87.3° 06:50	5.62	100%	92.3°
2033-05-15 Sun	49	—	unknown	01:50–04:05 (good, 2.25 h)	87.3° 06:45	5.56	98%	84.8°
2033-05-16 Mon	47	—	unknown	02:05–04:05 (good, 2.0 h)	87.3° 06:40	5.51	94%	77.4°
2033-05-17 Tue	47	—	unknown	01:50–04:05 (good, 2.25 h)	87.3° 06:35	5.46	87%	70.4°
2033-05-18 Wed	49	—	unknown	00:50–04:00 (good, 3.17 h)	87.3° 06:35	5.41	80%	64.0°
2033-05-19 Thu	64	—	unknown	00:15–04:00 (good, 3.75 h)	87.3° 06:30	5.35	70%	58.7°
2033-05-20 Fri	74	—	unknown	00:10–04:00 (good, 3.83 h)	87.3° 06:25	5.3	60%	55.2°
2033-05-21 Sat	85	—	unknown	00:05–04:00 (good, 3.92 h)	87.3° 06:20	5.26	48%	53.8°
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°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-05-10&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.