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: 01-02 (54), 01-03 (49), 01-04 (44), 01-05 (37), 01-06 (32) — by astronomy; check the weather when the night is within four days.

2044-01-02astronomy score per night — click a bar for that night2044-01-31

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2044-01-02 Sat	54	—	unknown	18:45–20:55 (good, 2.17 h)	87.3° 14:35	11.44	6%	65.2°
2044-01-03 Sun	49	—	unknown	18:45–20:50 (good, 2.08 h)	87.3° 14:30	11.43	11%	61.4°
2044-01-04 Mon	44	—	unknown	18:45–20:40 (good, 1.92 h)	87.2° 14:25	11.42	18%	59.0°
2044-01-05 Tue	37	—	unknown	18:45–20:30 (good, 1.75 h)	87.2° 14:20	11.41	27%	58.2°
2044-01-06 Wed	32	—	unknown	18:45–20:20 (good, 1.58 h)	87.2° 14:20	11.39	37%	59.2°
2044-01-07 Thu	26	—	unknown	18:50–20:05 (good, 1.25 h)	87.3° 14:15	11.38	47%	62.0°
2044-01-08 Fri	21	—	unknown	18:50–19:10 (good, 0.33 h)	87.3° 14:10	11.36	58%	66.5°
2044-01-09 Sat	18	—	unknown	18:50–20:55 (marginal, 2.08 h)	87.2° 14:05	11.35	69%	72.3°
2044-01-10 Sun	17	—	unknown	18:50–20:45 (marginal, 1.92 h)	87.2° 14:05	11.33	80%	79.3°
2044-01-11 Mon	17	—	unknown	18:50–20:45 (marginal, 1.92 h)	87.3° 14:00	11.31	88%	86.9°
2044-01-12 Tue	18	—	unknown	18:55–19:10 (good, 0.25 h)	87.3° 13:55	11.29	95%	94.7°
2044-01-13 Wed	21	—	unknown	18:55–19:40 (good, 0.75 h)	87.3° 13:50	11.27	99%	102.4°
2044-01-14 Thu	23	—	unknown	18:55–19:45 (good, 0.83 h)	87.2° 13:45	11.25	100%	109.4°
2044-01-15 Fri	25	—	unknown	18:55–19:50 (good, 0.92 h)	87.2° 13:45	11.23	98%	115.2°
2044-01-16 Sat	28	—	unknown	18:55–19:50 (good, 0.92 h)	87.3° 13:40	11.21	94%	119.3°
2044-01-17 Sun	27	—	unknown	19:00–19:55 (good, 0.92 h)	87.3° 13:35	11.19	87%	121.5°
2044-01-18 Mon	26	—	unknown	19:00–19:50 (good, 0.83 h)	87.3° 13:30	11.17	79%	121.7°
2044-01-19 Tue	25	—	unknown	19:00–19:45 (good, 0.75 h)	87.2° 13:25	11.14	70%	120.0°
2044-01-20 Wed	24	—	unknown	19:00–19:45 (good, 0.75 h)	87.2° 13:25	11.12	60%	116.8°
2044-01-21 Thu	23	—	unknown	19:00–19:40 (good, 0.67 h)	87.3° 13:20	11.09	50%	112.5°
2044-01-22 Fri	21	—	unknown	19:05–19:35 (good, 0.5 h)	87.3° 13:15	11.07	41%	107.3°
2044-01-23 Sat	19	—	unknown	19:05–19:30 (good, 0.42 h)	87.2° 13:10	11.04	32%	101.6°
2044-01-24 Sun	18	—	unknown	19:05–19:30 (good, 0.42 h)	87.2° 13:10	11.01	24%	95.6°
2044-01-25 Mon	16	—	unknown	19:05–19:25 (good, 0.33 h)	87.3° 13:05	10.98	16%	89.4°
2044-01-26 Tue	15	—	unknown	19:05–19:20 (good, 0.25 h)	87.3° 13:00	10.95	10%	83.2°
2044-01-27 Wed	13	—	unknown	19:10–19:15 (good, 0.08 h)	87.3° 12:55	10.93	5%	77.1°
2044-01-28 Thu	12	—	unknown	18:35–19:45 (marginal, 1.17 h)	87.2° 12:50	10.9	2%	71.4°
2044-01-29 Fri	11	—	unknown	18:40–19:45 (marginal, 1.08 h)	87.2° 12:50	10.86	0%	66.3°
2044-01-30 Sat	11	—	unknown	19:10–19:40 (marginal, 0.5 h)	87.3° 12:45	10.83	1%	62.2°
2044-01-31 Sun	9	—	unknown	19:15–19:35 (marginal, 0.33 h)	87.3° 12:40	10.8	3%	59.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2044-01-02&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.