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 Triangulum Pinwheel: 05-28 (1), 05-30 (1), 05-31 (1) — by astronomy; check the weather when the night is within four days.

2033-05-02astronomy score per night — click a bar for that night2033-05-31

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-05-02 Mon	0	—	unknown	—	79.1° 12:15	6.29	18%	63.8°
2033-05-03 Tue	0	—	unknown	—	79.1° 12:10	6.23	27%	76.1°
2033-05-04 Wed	0	—	unknown	—	79.1° 12:05	6.17	37%	88.0°
2033-05-05 Thu	0	—	unknown	—	79.1° 12:00	6.12	46%	99.6°
2033-05-06 Fri	0	—	unknown	—	79.1° 11:55	6.06	56%	110.9°
2033-05-07 Sat	0	—	unknown	—	79.1° 11:50	6.0	66%	122.0°
2033-05-08 Sun	0	—	unknown	—	79.1° 11:45	5.95	74%	132.6°
2033-05-09 Mon	0	—	unknown	—	79.1° 11:45	5.89	82%	142.7°
2033-05-10 Tue	0	—	unknown	—	79.1° 11:40	5.83	89%	151.7°
2033-05-11 Wed	0	—	unknown	—	79.1° 11:35	5.78	94%	158.1°
2033-05-12 Thu	0	—	unknown	—	79.1° 11:30	5.72	98%	159.2°
2033-05-13 Fri	0	—	unknown	—	79.1° 11:25	5.67	100%	154.1°
2033-05-14 Sat	0	—	unknown	—	79.1° 11:25	5.62	100%	145.3°
2033-05-15 Sun	0	—	unknown	—	79.1° 11:20	5.56	98%	134.7°
2033-05-16 Mon	0	—	unknown	—	79.1° 11:15	5.51	94%	123.2°
2033-05-17 Tue	0	—	unknown	—	79.1° 11:10	5.46	87%	111.2°
2033-05-18 Wed	0	—	unknown	—	79.1° 11:10	5.41	80%	98.8°
2033-05-19 Thu	0	—	unknown	—	79.1° 11:05	5.35	70%	86.2°
2033-05-20 Fri	0	—	unknown	—	79.1° 11:00	5.3	60%	73.4°
2033-05-21 Sat	0	—	unknown	—	79.1° 10:55	5.26	48%	60.5°
2033-05-22 Sun	0	—	unknown	—	79.1° 10:50	5.21	37%	47.7°
2033-05-23 Mon	0	—	unknown	—	79.1° 10:50	5.16	26%	35.6°
2033-05-24 Tue	0	—	unknown	—	79.1° 10:45	5.11	16%	25.3°
2033-05-25 Wed	0	—	unknown	—	79.1° 10:40	5.07	9%	20.4°
2033-05-26 Thu	0	—	unknown	—	79.1° 10:35	5.02	3%	24.5°
2033-05-27 Fri	0	—	unknown	—	79.1° 10:30	4.98	0%	34.4°
2033-05-28 Sat	1	—	unknown	—	79.1° 10:30	4.94	0%	46.3°
2033-05-29 Sun	0	—	unknown	—	79.1° 10:25	4.9	3%	58.7°
2033-05-30 Mon	1	—	unknown	—	79.1° 10:20	4.86	8%	71.2°
2033-05-31 Tue	1	—	unknown	—	79.1° 10:15	4.82	14%	83.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-05-02&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.