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 Seven Sisters: 03-04 (45), 03-15 (41), 03-16 (41), 03-17 (39), 03-14 (38) — by astronomy; check the weather when the night is within four days.

2044-03-04astronomy score per night — click a bar for that night2044-04-02

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2044-03-04 Fri	45	—	unknown	19:50–22:15 (good, 2.42 h)	72.5° 17:20	9.48	28%	10.3°
2044-03-05 Sat	35	—	unknown	19:50–22:00 (good, 2.17 h)	72.6° 17:15	9.43	39%	3.8°
2044-03-06 Sun	24	—	unknown	19:55–22:45 (marginal, 2.83 h)	72.6° 17:10	9.38	51%	17.9°
2044-03-07 Mon	17	—	unknown	19:55–22:25 (marginal, 2.5 h)	72.6° 17:05	9.34	62%	32.0°
2044-03-08 Tue	15	—	unknown	19:55–22:20 (marginal, 2.42 h)	72.5° 17:00	9.29	73%	46.2°
2044-03-09 Wed	16	—	unknown	19:55–22:15 (marginal, 2.33 h)	72.6° 17:00	9.24	82%	60.3°
2044-03-10 Thu	19	—	unknown	19:55–22:15 (marginal, 2.33 h)	72.6° 16:55	9.19	90%	74.4°
2044-03-11 Fri	24	—	unknown	20:00–20:30 (good, 0.5 h)	72.6° 16:50	9.14	96%	88.4°
2044-03-12 Sat	30	—	unknown	20:00–21:30 (good, 1.5 h)	72.6° 16:45	9.09	99%	102.1°
2044-03-13 Sun	36	—	unknown	20:00–21:40 (good, 1.67 h)	72.5° 16:45	9.04	100%	115.6°
2044-03-14 Mon	38	—	unknown	20:00–21:40 (good, 1.67 h)	72.6° 16:40	8.99	99%	128.9°
2044-03-15 Tue	41	—	unknown	20:05–21:40 (good, 1.58 h)	72.6° 16:35	8.94	95%	141.8°
2044-03-16 Wed	41	—	unknown	20:05–21:40 (good, 1.58 h)	72.6° 16:30	8.89	90%	154.5°
2044-03-17 Thu	39	—	unknown	20:05–21:40 (good, 1.58 h)	72.6° 16:25	8.84	83%	166.8°
2044-03-18 Fri	37	—	unknown	20:05–21:35 (good, 1.5 h)	72.5° 16:25	8.79	75%	178.7°
2044-03-19 Sat	34	—	unknown	20:10–21:30 (good, 1.33 h)	72.6° 16:20	8.74	66%	169.0°
2044-03-20 Sun	33	—	unknown	20:10–21:25 (good, 1.25 h)	72.6° 16:15	8.69	57%	157.2°
2044-03-21 Mon	31	—	unknown	20:10–21:20 (good, 1.17 h)	72.6° 16:10	8.64	48%	145.4°
2044-03-22 Tue	30	—	unknown	20:10–21:20 (good, 1.17 h)	72.5° 16:05	8.58	38%	133.5°
2044-03-23 Wed	27	—	unknown	20:15–21:15 (good, 1.0 h)	72.6° 16:05	8.53	29%	121.4°
2044-03-24 Thu	26	—	unknown	20:15–21:10 (good, 0.92 h)	72.6° 16:00	8.48	21%	109.1°
2044-03-25 Fri	25	—	unknown	20:15–21:05 (good, 0.83 h)	72.6° 15:55	8.43	13%	96.6°
2044-03-26 Sat	23	—	unknown	20:15–21:00 (good, 0.75 h)	72.6° 15:50	8.37	7%	83.7°
2044-03-27 Sun	21	—	unknown	21:20–22:00 (good, 0.67 h)	72.5° 16:50	8.32	3%	70.4°
2044-03-28 Mon	19	—	unknown	21:20–21:55 (good, 0.58 h)	72.6° 16:45	8.27	0%	56.8°
2044-03-29 Tue	18	—	unknown	21:20–21:50 (good, 0.5 h)	72.6° 16:40	8.21	0%	42.8°
2044-03-30 Wed	15	—	unknown	21:25–21:45 (good, 0.33 h)	72.6° 16:35	8.16	3%	28.7°
2044-03-31 Thu	12	—	unknown	21:25–21:40 (good, 0.25 h)	72.6° 16:30	8.1	8%	14.3°
2044-04-01 Fri	9	—	unknown	21:25–21:30 (good, 0.08 h)	72.5° 16:30	8.05	16%	0.8°
2044-04-02 Sat	7	—	unknown	21:25–22:00 (marginal, 0.58 h)	72.6° 16:25	7.99	25%	14.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2044-03-04&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.