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: 08-24 (100), 08-25 (100), 08-26 (100), 08-27 (100), 08-28 (100) — by astronomy; check the weather when the night is within four days.

2033-08-24astronomy score per night — click a bar for that night2033-09-22

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-08-24 Wed	100	—	unknown	23:15–05:00 (good, 5.75 h)	79.1° 04:40	7.18	0%	118.6°
2033-08-25 Thu	100	—	unknown	23:10–05:05 (good, 5.92 h)	79.1° 04:40	7.23	1%	129.5°
2033-08-26 Fri	100	—	unknown	23:05–05:05 (good, 6.0 h)	79.1° 04:35	7.29	4%	139.8°
2033-08-27 Sat	100	—	unknown	23:05–05:05 (good, 6.0 h)	79.1° 04:30	7.35	8%	149.0°
2033-08-28 Sun	100	—	unknown	23:00–05:05 (good, 6.08 h)	79.1° 04:25	7.4	14%	156.1°
2033-08-29 Mon	100	—	unknown	22:55–05:10 (good, 6.25 h)	79.1° 04:25	7.46	21%	158.9°
2033-08-30 Tue	100	—	unknown	22:50–05:10 (good, 6.33 h)	79.1° 04:20	7.52	30%	155.7°
2033-08-31 Wed	100	—	unknown	22:50–05:10 (good, 6.33 h)	79.1° 04:15	7.57	39%	148.2°
2033-09-01 Thu	100	—	unknown	22:50–05:10 (good, 6.33 h)	79.1° 04:10	7.63	48%	138.5°
2033-09-02 Fri	100	—	unknown	22:45–05:15 (good, 6.5 h)	79.1° 04:05	7.68	58%	127.7°
2033-09-03 Sat	100	—	unknown	22:45–05:15 (good, 6.5 h)	79.1° 04:05	7.74	68%	116.1°
2033-09-04 Sun	100	—	unknown	22:45–05:15 (good, 6.5 h)	79.1° 04:00	7.79	78%	103.8°
2033-09-05 Mon	100	—	unknown	22:55–05:20 (good, 6.42 h)	79.1° 03:55	7.85	86%	91.0°
2033-09-06 Tue	100	—	unknown	00:15–05:20 (good, 5.08 h)	79.1° 03:50	7.9	93%	77.8°
2033-09-07 Wed	70	—	unknown	02:55–05:20 (good, 2.42 h)	79.1° 03:45	7.96	98%	64.3°
2033-09-08 Thu	51	—	unknown	22:15–05:20 (marginal, 7.08 h)	79.1° 03:45	8.01	100%	50.8°
2033-09-09 Fri	33	—	unknown	22:15–05:25 (marginal, 7.17 h)	79.1° 03:40	8.07	99%	37.9°
2033-09-10 Sat	26	—	unknown	22:05–05:25 (marginal, 7.33 h)	79.1° 03:35	8.12	95%	26.9°
2033-09-11 Sun	35	—	unknown	21:50–05:25 (marginal, 7.58 h)	79.1° 03:30	8.18	88%	21.2°
2033-09-12 Mon	52	—	unknown	21:30–05:25 (marginal, 7.92 h)	79.1° 03:30	8.23	80%	24.5°
2033-09-13 Tue	82	—	unknown	22:50–01:25 (good, 2.58 h)	79.1° 03:25	8.28	70%	33.8°
2033-09-14 Wed	88	—	unknown	21:50–05:30 (good, 7.67 h)	79.1° 03:20	8.34	59%	45.2°
2033-09-15 Thu	95	—	unknown	21:50–05:30 (good, 7.67 h)	79.1° 03:15	8.39	48%	57.2°
2033-09-16 Fri	100	—	unknown	21:45–05:30 (good, 7.75 h)	79.1° 03:10	8.44	37%	69.3°
2033-09-17 Sat	100	—	unknown	21:40–05:35 (good, 7.92 h)	79.1° 03:10	8.49	28%	81.2°
2033-09-18 Sun	100	—	unknown	21:35–05:35 (good, 8.0 h)	79.1° 03:05	8.54	19%	92.9°
2033-09-19 Mon	100	—	unknown	21:35–05:35 (good, 8.0 h)	79.1° 03:00	8.6	12%	104.4°
2033-09-20 Tue	100	—	unknown	21:30–05:35 (good, 8.08 h)	79.1° 02:55	8.65	6%	115.7°
2033-09-21 Wed	100	—	unknown	21:25–05:40 (good, 8.25 h)	79.1° 02:50	8.7	2%	126.6°
2033-09-22 Thu	100	—	unknown	21:20–05:40 (good, 8.33 h)	79.1° 02:50	8.75	0%	137.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-08-24&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.