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 Andromeda Galaxy: 02-16 (46), 02-17 (45), 02-18 (43), 02-14 (42), 02-15 (42) — by astronomy; check the weather when the night is within four days.

2033-02-09astronomy score per night — click a bar for that night2033-03-10

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-02-09 Wed	24	—	unknown	19:25–22:10 (marginal, 2.75 h)	89.7° 15:45	10.47	82%	71.7°
2033-02-10 Thu	26	—	unknown	19:25–19:35 (good, 0.17 h)	89.6° 15:40	10.43	89%	82.0°
2033-02-11 Fri	30	—	unknown	19:25–20:25 (good, 1.0 h)	89.5° 15:40	10.39	95%	92.3°
2033-02-12 Sat	34	—	unknown	19:25–21:10 (good, 1.75 h)	89.7° 15:35	10.35	98%	102.4°
2033-02-13 Sun	38	—	unknown	19:30–21:20 (good, 1.83 h)	89.8° 15:30	10.31	100%	112.2°
2033-02-14 Mon	42	—	unknown	19:30–21:20 (good, 1.83 h)	89.7° 15:25	10.27	100%	121.6°
2033-02-15 Tue	42	—	unknown	19:30–21:20 (good, 1.83 h)	89.5° 15:20	10.23	98%	130.3°
2033-02-16 Wed	46	—	unknown	19:30–21:20 (good, 1.83 h)	89.6° 15:20	10.19	94%	137.7°
2033-02-17 Thu	45	—	unknown	19:35–21:15 (good, 1.67 h)	89.7° 15:15	10.15	88%	143.4°
2033-02-18 Fri	43	—	unknown	19:35–21:20 (good, 1.75 h)	89.7° 15:10	10.11	82%	146.2°
2033-02-19 Sat	42	—	unknown	19:35–21:15 (good, 1.67 h)	89.6° 15:05	10.07	74%	145.4°
2033-02-20 Sun	40	—	unknown	19:35–21:10 (good, 1.58 h)	89.5° 15:00	10.03	65%	141.2°
2033-02-21 Mon	38	—	unknown	19:35–21:05 (good, 1.5 h)	89.6° 15:00	9.99	56%	134.3°
2033-02-22 Tue	36	—	unknown	19:40–21:05 (good, 1.42 h)	89.7° 14:55	9.94	46%	125.7°
2033-02-23 Wed	35	—	unknown	19:40–21:00 (good, 1.33 h)	89.7° 14:50	9.9	35%	115.8°
2033-02-24 Thu	33	—	unknown	19:40–20:55 (good, 1.25 h)	89.6° 14:45	9.86	25%	104.9°
2033-02-25 Fri	31	—	unknown	19:40–20:50 (good, 1.17 h)	89.5° 14:45	9.81	16%	93.4°
2033-02-26 Sat	29	—	unknown	19:45–20:50 (good, 1.08 h)	89.7° 14:40	9.77	9%	81.4°
2033-02-27 Sun	27	—	unknown	19:45–20:45 (good, 1.0 h)	89.8° 14:35	9.72	3%	69.3°
2033-02-28 Mon	26	—	unknown	19:45–20:40 (good, 0.92 h)	89.7° 14:30	9.68	0%	57.5°
2033-03-01 Tue	24	—	unknown	19:45–20:35 (good, 0.83 h)	89.5° 14:25	9.63	1%	46.7°
2033-03-02 Wed	22	—	unknown	19:50–20:30 (good, 0.67 h)	89.6° 14:25	9.59	4%	38.3°
2033-03-03 Thu	19	—	unknown	19:50–20:25 (good, 0.58 h)	89.7° 14:20	9.54	10%	34.0°
2033-03-04 Fri	15	—	unknown	19:50–20:15 (good, 0.42 h)	89.8° 14:15	9.49	18%	35.1°
2033-03-05 Sat	13	—	unknown	19:50–20:00 (good, 0.17 h)	89.6° 14:10	9.45	28%	41.0°
2033-03-06 Sun	10	—	unknown	19:20–20:50 (marginal, 1.5 h)	89.5° 14:05	9.4	38%	49.4°
2033-03-07 Mon	7	—	unknown	19:55–20:45 (marginal, 0.83 h)	89.6° 14:05	9.35	49%	59.1°
2033-03-08 Tue	6	—	unknown	19:55–20:40 (marginal, 0.75 h)	89.7° 14:00	9.31	59%	69.3°
2033-03-09 Wed	5	—	unknown	19:55–20:35 (marginal, 0.67 h)	89.7° 13:55	9.26	69%	79.6°
2033-03-10 Thu	5	—	unknown	19:55–20:30 (marginal, 0.58 h)	89.6° 13:50	9.21	78%	89.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-02-09&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.