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: 07-15 (55), 07-16 (55), 07-14 (53), 07-13 (51), 07-17 (51) — by astronomy; check the weather when the night is within four days.

2035-06-23astronomy score per night — click a bar for that night2035-07-22

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2035-06-23 Sat	8	—	unknown	02:55–03:40 (marginal, 0.75 h)	79.1° 08:50	4.43	91%	86.1°
2035-06-24 Sun	8	—	unknown	02:50–03:40 (marginal, 0.83 h)	79.1° 08:45	4.43	85%	75.1°
2035-06-25 Mon	9	—	unknown	02:50–03:40 (marginal, 0.83 h)	79.1° 08:40	4.44	78%	64.0°
2035-06-26 Tue	10	—	unknown	02:45–03:40 (marginal, 0.92 h)	79.1° 08:35	4.45	69%	53.0°
2035-06-27 Wed	11	—	unknown	02:40–03:40 (marginal, 1.0 h)	79.1° 08:30	4.47	59%	42.3°
2035-06-28 Thu	14	—	unknown	02:30–04:35 (marginal, 2.08 h)	79.1° 08:30	4.48	48%	32.5°
2035-06-29 Fri	17	—	unknown	03:15–03:40 (good, 0.42 h)	79.1° 08:25	4.5	38%	25.3°
2035-06-30 Sat	21	—	unknown	03:05–03:45 (good, 0.67 h)	79.1° 08:20	4.51	27%	23.9°
2035-07-01 Sun	27	—	unknown	02:50–03:45 (good, 0.92 h)	79.1° 08:15	4.53	17%	29.8°
2035-07-02 Mon	31	—	unknown	02:45–03:45 (good, 1.0 h)	79.1° 08:15	4.56	9%	40.1°
2035-07-03 Tue	32	—	unknown	02:40–03:45 (good, 1.08 h)	79.1° 08:10	4.58	4%	52.6°
2035-07-04 Wed	34	—	unknown	02:35–03:45 (good, 1.17 h)	79.1° 08:05	4.61	0%	66.0°
2035-07-05 Thu	35	—	unknown	02:35–03:45 (good, 1.17 h)	79.1° 08:00	4.63	0%	79.8°
2035-07-06 Fri	38	—	unknown	02:30–03:50 (good, 1.33 h)	79.1° 07:55	4.66	4%	93.6°
2035-07-07 Sat	40	—	unknown	02:25–03:50 (good, 1.42 h)	79.1° 07:55	4.69	9%	107.0°
2035-07-08 Sun	41	—	unknown	02:20–03:50 (good, 1.5 h)	79.1° 07:50	4.73	17%	119.9°
2035-07-09 Mon	43	—	unknown	02:20–03:50 (good, 1.5 h)	79.1° 07:45	4.76	26%	131.8°
2035-07-10 Tue	46	—	unknown	02:15–03:55 (good, 1.67 h)	79.1° 07:40	4.79	36%	142.6°
2035-07-11 Wed	48	—	unknown	02:10–03:55 (good, 1.75 h)	79.1° 07:35	4.83	46%	151.2°
2035-07-12 Thu	50	—	unknown	02:05–03:55 (good, 1.83 h)	79.1° 07:35	4.87	56%	156.0°
2035-07-13 Fri	51	—	unknown	02:00–03:55 (good, 1.92 h)	79.1° 07:30	4.91	66%	155.2°
2035-07-14 Sat	53	—	unknown	02:05–04:00 (good, 1.92 h)	79.1° 07:25	4.95	75%	149.5°
2035-07-15 Sun	55	—	unknown	02:00–04:00 (good, 2.0 h)	79.1° 07:20	4.99	82%	141.1°
2035-07-16 Mon	55	—	unknown	02:00–04:00 (good, 2.0 h)	79.1° 07:20	5.03	89%	131.5°
2035-07-17 Tue	51	—	unknown	01:55–04:00 (good, 2.08 h)	79.1° 07:15	5.08	94%	121.3°
2035-07-18 Wed	47	—	unknown	02:00–04:05 (good, 2.08 h)	79.1° 07:10	5.12	98%	110.7°
2035-07-19 Thu	41	—	unknown	02:05–04:05 (good, 2.0 h)	79.1° 07:05	5.17	100%	99.8°
2035-07-20 Fri	36	—	unknown	02:35–04:05 (good, 1.5 h)	79.1° 07:00	5.22	100%	88.8°
2035-07-21 Sat	31	—	unknown	03:30–04:10 (good, 0.67 h)	79.1° 07:00	5.26	98%	77.8°
2035-07-22 Sun	26	—	unknown	01:10–04:10 (marginal, 3.0 h)	79.1° 06:55	5.31	94%	66.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-06-23&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.