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: 09-14 (100), 09-15 (100), 09-16 (100), 09-17 (100), 09-18 (100) — by astronomy; check the weather when the night is within four days.

2036-09-04astronomy score per night — click a bar for that night2036-10-03

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-09-04 Thu	67	—	unknown	03:35–05:15 (good, 1.67 h)	79.1° 04:00	7.81	99%	62.1°
2036-09-05 Fri	51	—	unknown	22:20–05:20 (marginal, 7.0 h)	79.2° 03:55	7.86	100%	51.7°
2036-09-06 Sat	38	—	unknown	22:20–05:20 (marginal, 7.0 h)	79.2° 03:50	7.92	99%	41.8°
2036-09-07 Sun	29	—	unknown	22:15–05:20 (marginal, 7.08 h)	79.2° 03:45	7.97	96%	32.9°
2036-09-08 Mon	33	—	unknown	22:00–05:20 (marginal, 7.33 h)	79.1° 03:40	8.03	91%	26.4°
2036-09-09 Tue	43	—	unknown	21:40–05:25 (marginal, 7.75 h)	79.1° 03:40	8.08	84%	24.5°
2036-09-10 Wed	71	—	unknown	22:05–22:25 (good, 0.33 h)	79.2° 03:35	8.14	76%	28.4°
2036-09-11 Thu	83	—	unknown	22:05–02:30 (good, 4.42 h)	79.2° 03:30	8.19	66%	36.6°
2036-09-12 Fri	89	—	unknown	22:00–05:25 (good, 7.42 h)	79.1° 03:25	8.24	56%	47.0°
2036-09-13 Sat	95	—	unknown	21:55–05:30 (good, 7.58 h)	79.1° 03:25	8.3	44%	58.6°
2036-09-14 Sun	100	—	unknown	21:50–05:30 (good, 7.67 h)	79.2° 03:20	8.35	34%	71.1°
2036-09-15 Mon	100	—	unknown	21:45–05:30 (good, 7.75 h)	79.2° 03:15	8.4	23%	84.1°
2036-09-16 Tue	100	—	unknown	21:45–05:30 (good, 7.75 h)	79.2° 03:10	8.45	14%	97.4°
2036-09-17 Wed	100	—	unknown	21:40–05:35 (good, 7.92 h)	79.1° 03:05	8.51	7%	110.8°
2036-09-18 Thu	100	—	unknown	21:35–05:35 (good, 8.0 h)	79.1° 03:05	8.56	2%	124.0°
2036-09-19 Fri	100	—	unknown	21:30–05:35 (good, 8.08 h)	79.2° 03:00	8.61	0%	136.5°
2036-09-20 Sat	100	—	unknown	21:30–05:35 (good, 8.08 h)	79.2° 02:55	8.66	1%	147.3°
2036-09-21 Sun	100	—	unknown	21:25–05:40 (good, 8.25 h)	79.2° 02:50	8.71	5%	154.4°
2036-09-22 Mon	100	—	unknown	21:20–05:40 (good, 8.33 h)	79.1° 02:45	8.76	11%	154.9°
2036-09-23 Tue	100	—	unknown	21:15–05:40 (good, 8.42 h)	79.1° 02:45	8.81	19%	149.1°
2036-09-24 Wed	100	—	unknown	21:15–05:40 (good, 8.42 h)	79.2° 02:40	8.86	27%	140.1°
2036-09-25 Thu	100	—	unknown	21:10–05:45 (good, 8.58 h)	79.2° 02:35	8.91	37%	129.8°
2036-09-26 Fri	100	—	unknown	21:10–05:45 (good, 8.58 h)	79.1° 02:30	8.96	47%	119.1°
2036-09-27 Sat	100	—	unknown	21:10–05:45 (good, 8.58 h)	79.1° 02:30	9.01	56%	108.3°
2036-09-28 Sun	100	—	unknown	21:10–05:45 (good, 8.58 h)	79.2° 02:25	9.06	66%	97.4°
2036-09-29 Mon	100	—	unknown	21:15–05:45 (good, 8.5 h)	79.2° 02:20	9.11	74%	86.7°
2036-09-30 Tue	100	—	unknown	22:00–05:50 (good, 7.83 h)	79.2° 02:15	9.16	82%	75.9°
2036-10-01 Wed	100	—	unknown	23:30–05:50 (good, 6.33 h)	79.1° 02:10	9.21	89%	65.2°
2036-10-02 Thu	95	—	unknown	02:55–05:50 (good, 2.92 h)	79.1° 02:10	9.25	94%	54.7°
2036-10-03 Fri	58	—	unknown	20:35–05:50 (marginal, 9.25 h)	79.2° 02:05	9.3	98%	44.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-09-04&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.