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: 09-15 (100), 09-16 (100), 09-17 (100), 09-18 (100), 09-19 (100) — by astronomy; check the weather when the night is within four days.

2034-09-15astronomy score per night — click a bar for that night2034-10-14

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
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°
2034-09-27 Wed	43	—	unknown	21:05–05:45 (marginal, 8.67 h)	79.1° 02:30	8.99	100%	36.5°
2034-09-28 Thu	30	—	unknown	21:00–00:55 (marginal, 3.92 h)	79.1° 02:25	9.04	99%	26.8°
2034-09-29 Fri	36	—	unknown	20:40–02:30 (marginal, 5.83 h)	79.1° 02:20	9.09	95%	22.6°
2034-09-30 Sat	60	—	unknown	20:50–20:55 (good, 0.08 h)	79.1° 02:20	9.13	89%	26.8°
2034-10-01 Sun	83	—	unknown	20:45–21:40 (good, 0.92 h)	79.1° 02:15	9.18	80%	36.6°
2034-10-02 Mon	89	—	unknown	20:45–02:40 (good, 5.92 h)	79.1° 02:10	9.23	70%	48.4°
2034-10-03 Tue	97	—	unknown	20:40–05:50 (good, 9.17 h)	79.1° 02:05	9.28	59%	61.0°
2034-10-04 Wed	100	—	unknown	20:35–05:50 (good, 9.25 h)	79.1° 02:00	9.33	48%	73.6°
2034-10-05 Thu	100	—	unknown	20:30–05:55 (good, 9.42 h)	79.1° 02:00	9.37	37%	86.2°
2034-10-06 Fri	100	—	unknown	20:30–05:55 (good, 9.42 h)	79.1° 01:55	9.42	27%	98.5°
2034-10-07 Sat	100	—	unknown	20:30–05:55 (good, 9.42 h)	79.1° 01:50	9.47	18%	110.5°
2034-10-08 Sun	100	—	unknown	20:25–05:55 (good, 9.5 h)	79.1° 01:45	9.51	11%	122.2°
2034-10-09 Mon	100	—	unknown	20:25–06:00 (good, 9.58 h)	79.1° 01:40	9.56	6%	133.2°
2034-10-10 Tue	100	—	unknown	20:25–06:00 (good, 9.58 h)	79.1° 01:40	9.6	2%	143.4°
2034-10-11 Wed	100	—	unknown	20:20–06:00 (good, 9.67 h)	79.1° 01:35	9.65	0%	151.8°
2034-10-12 Thu	100	—	unknown	20:20–06:00 (good, 9.67 h)	79.1° 01:30	9.69	0%	156.8°
2034-10-13 Fri	100	—	unknown	20:20–06:00 (good, 9.67 h)	79.1° 01:25	9.74	2%	156.4°
2034-10-14 Sat	100	—	unknown	20:15–06:05 (good, 9.83 h)	79.1° 01:25	9.78	6%	150.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-09-15&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.