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 V1057 Cyg: 02-25 (25), 02-26 (25), 02-27 (24), 03-05 (24), 03-06 (24) — by astronomy; check the weather when the night is within four days.

2045-02-05astronomy score per night — click a bar for that night2045-03-06

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2045-02-05 Sun	8	—	unknown	05:25–05:55 (marginal, 0.5 h)	87.2° 12:20	10.61	78%	120.0°
2045-02-06 Mon	8	—	unknown	05:20–05:55 (marginal, 0.58 h)	87.2° 12:15	10.57	69%	115.4°
2045-02-07 Tue	9	—	unknown	05:15–05:55 (marginal, 0.67 h)	87.3° 12:10	10.54	59%	109.8°
2045-02-08 Wed	9	—	unknown	05:10–05:50 (marginal, 0.67 h)	87.3° 12:05	10.5	48%	103.6°
2045-02-09 Thu	9	—	unknown	05:10–06:25 (marginal, 1.25 h)	87.2° 12:00	10.46	39%	97.0°
2045-02-10 Fri	10	—	unknown	05:45–05:50 (good, 0.08 h)	87.3° 11:55	10.42	30%	90.3°
2045-02-11 Sat	11	—	unknown	05:40–05:50 (good, 0.17 h)	87.3° 11:50	10.39	21%	83.7°
2045-02-12 Sun	13	—	unknown	05:30–05:50 (good, 0.33 h)	87.2° 11:45	10.35	14%	77.4°
2045-02-13 Mon	14	—	unknown	05:25–05:45 (good, 0.33 h)	87.2° 11:40	10.31	8%	71.5°
2045-02-14 Tue	15	—	unknown	05:25–05:45 (good, 0.33 h)	87.2° 11:40	10.27	4%	66.2°
2045-02-15 Wed	16	—	unknown	05:20–05:45 (good, 0.42 h)	87.3° 11:35	10.23	1%	61.7°
2045-02-16 Thu	17	—	unknown	05:15–05:45 (good, 0.5 h)	87.3° 11:30	10.19	0%	58.5°
2045-02-17 Fri	17	—	unknown	05:10–05:40 (good, 0.5 h)	87.2° 11:25	10.15	1%	56.7°
2045-02-18 Sat	18	—	unknown	05:10–05:40 (good, 0.5 h)	87.2° 11:25	10.11	4%	56.5°
2045-02-19 Sun	20	—	unknown	05:05–05:40 (good, 0.58 h)	87.2° 11:20	10.07	8%	58.1°
2045-02-20 Mon	21	—	unknown	05:00–05:40 (good, 0.67 h)	87.3° 11:15	10.02	14%	61.3°
2045-02-21 Tue	21	—	unknown	04:55–05:35 (good, 0.67 h)	87.3° 11:10	9.98	22%	65.9°
2045-02-22 Wed	22	—	unknown	04:50–05:35 (good, 0.75 h)	87.2° 11:05	9.94	32%	71.8°
2045-02-23 Thu	23	—	unknown	04:50–05:35 (good, 0.75 h)	87.2° 11:05	9.9	42%	78.5°
2045-02-24 Fri	23	—	unknown	04:45–05:30 (good, 0.75 h)	87.3° 11:00	9.85	53%	85.8°
2045-02-25 Sat	25	—	unknown	04:40–05:30 (good, 0.83 h)	87.3° 10:55	9.81	64%	93.5°
2045-02-26 Sun	25	—	unknown	04:35–05:30 (good, 0.92 h)	87.2° 10:50	9.76	74%	101.3°
2045-02-27 Mon	24	—	unknown	04:45–05:25 (good, 0.67 h)	87.2° 10:45	9.72	84%	108.7°
2045-02-28 Tue	22	—	unknown	04:40–05:25 (good, 0.75 h)	87.2° 10:45	9.67	92%	115.2°
2045-03-01 Wed	23	—	unknown	04:35–05:25 (good, 0.83 h)	87.3° 10:40	9.63	97%	120.2°
2045-03-02 Thu	23	—	unknown	04:35–05:25 (good, 0.83 h)	87.3° 10:35	9.58	100%	123.1°
2045-03-03 Fri	23	—	unknown	04:30–05:20 (good, 0.83 h)	87.2° 10:30	9.54	99%	123.5°
2045-03-04 Sat	23	—	unknown	04:25–05:20 (good, 0.92 h)	87.2° 10:30	9.49	96%	121.5°
2045-03-05 Sun	24	—	unknown	04:25–05:20 (good, 0.92 h)	87.2° 10:25	9.44	91%	117.5°
2045-03-06 Mon	24	—	unknown	04:20–05:15 (good, 0.92 h)	87.3° 10:20	9.4	84%	112.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2045-02-05&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.