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: 09-07 (100), 09-08 (100), 09-09 (100), 09-10 (100), 09-11 (100) — by astronomy; check the weather when the night is within four days.

2034-08-28astronomy score per night — click a bar for that night2034-09-26

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-08-28 Mon	66	—	unknown	02:35–05:05 (good, 2.5 h)	79.1° 04:30	7.39	99%	67.8°
2034-08-29 Tue	48	—	unknown	22:50–05:10 (marginal, 6.33 h)	79.1° 04:25	7.45	100%	55.5°
2034-08-30 Wed	33	—	unknown	22:50–05:10 (marginal, 6.33 h)	79.1° 04:20	7.5	98%	43.4°
2034-08-31 Thu	25	—	unknown	22:45–05:10 (marginal, 6.42 h)	79.1° 04:15	7.56	94%	32.4°
2034-09-01 Fri	32	—	unknown	22:30–05:10 (marginal, 6.67 h)	79.1° 04:10	7.61	87%	24.4°
2034-09-02 Sat	44	—	unknown	22:10–05:15 (marginal, 7.08 h)	79.1° 04:10	7.67	78%	23.1°
2034-09-03 Sun	75	—	unknown	22:35–23:00 (good, 0.42 h)	79.1° 04:05	7.73	68%	29.4°
2034-09-04 Mon	85	—	unknown	22:35–05:15 (good, 6.67 h)	79.1° 04:00	7.78	56%	39.7°
2034-09-05 Tue	92	—	unknown	22:30–05:15 (good, 6.75 h)	79.1° 03:55	7.84	45%	51.5°
2034-09-06 Wed	99	—	unknown	22:25–05:20 (good, 6.92 h)	79.1° 03:50	7.89	34%	64.0°
2034-09-07 Thu	100	—	unknown	22:20–05:20 (good, 7.0 h)	79.1° 03:50	7.95	24%	76.6°
2034-09-08 Fri	100	—	unknown	22:15–05:20 (good, 7.08 h)	79.1° 03:45	8.0	15%	89.1°
2034-09-09 Sat	100	—	unknown	22:15–05:25 (good, 7.17 h)	79.1° 03:40	8.05	8%	101.5°
2034-09-10 Sun	100	—	unknown	22:10–05:25 (good, 7.25 h)	79.1° 03:35	8.11	3%	113.6°
2034-09-11 Mon	100	—	unknown	22:05–05:25 (good, 7.33 h)	79.1° 03:30	8.16	1%	125.3°
2034-09-12 Tue	100	—	unknown	22:00–05:25 (good, 7.42 h)	79.1° 03:30	8.22	0%	136.3°
2034-09-13 Wed	100	—	unknown	21:55–05:30 (good, 7.58 h)	79.1° 03:25	8.27	2%	146.1°
2034-09-14 Thu	100	—	unknown	21:55–05:30 (good, 7.58 h)	79.1° 03:20	8.32	5%	153.8°
2034-09-15 Fri	100	—	unknown	21:50–05:30 (good, 7.67 h)	79.1° 03:15	8.38	10%	157.3°
2034-09-16 Sat	100	—	unknown	21:45–05:30 (good, 7.75 h)	79.1° 03:15	8.43	17%	155.1°
2034-09-17 Sun	100	—	unknown	21:45–05:35 (good, 7.83 h)	79.1° 03:10	8.48	24%	148.6°
2034-09-18 Mon	100	—	unknown	21:40–05:35 (good, 7.92 h)	79.1° 03:05	8.53	33%	139.8°
2034-09-19 Tue	100	—	unknown	21:35–05:35 (good, 8.0 h)	79.1° 03:00	8.58	42%	129.8°
2034-09-20 Wed	100	—	unknown	21:35–05:35 (good, 8.0 h)	79.1° 02:55	8.64	51%	119.3°
2034-09-21 Thu	100	—	unknown	21:35–05:35 (good, 8.0 h)	79.1° 02:55	8.69	61%	108.3°
2034-09-22 Fri	100	—	unknown	21:40–05:40 (good, 8.0 h)	79.1° 02:50	8.74	71%	96.8°
2034-09-23 Sat	100	—	unknown	21:45–05:40 (good, 7.92 h)	79.1° 02:45	8.79	79%	85.0°
2034-09-24 Sun	100	—	unknown	23:10–05:40 (good, 6.5 h)	79.1° 02:40	8.84	87%	72.9°
2034-09-25 Mon	100	—	unknown	02:00–05:40 (good, 3.67 h)	79.1° 02:35	8.89	94%	60.6°
2034-09-26 Tue	61	—	unknown	04:55–05:45 (good, 0.83 h)	79.1° 02:35	8.94	98%	48.2°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-08-28&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.