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: 01-30 (90), 01-31 (86), 02-01 (83), 02-02 (80), 02-03 (79) — by astronomy; check the weather when the night is within four days.

2046-01-30astronomy score per night — click a bar for that night2046-02-28

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2046-01-30 Tue	90	—	unknown	19:10–22:35 (good, 3.42 h)	89.7° 16:25	10.82	32%	136.8°
2046-01-31 Wed	86	—	unknown	19:15–22:30 (good, 3.25 h)	89.5° 16:20	10.79	22%	126.9°
2046-02-01 Thu	83	—	unknown	19:15–22:25 (good, 3.17 h)	89.7° 16:20	10.75	15%	116.5°
2046-02-02 Fri	80	—	unknown	19:15–22:25 (good, 3.17 h)	89.8° 16:15	10.72	8%	105.8°
2046-02-03 Sat	79	—	unknown	19:15–22:20 (good, 3.08 h)	89.8° 16:10	10.69	4%	95.1°
2046-02-04 Sun	76	—	unknown	19:20–22:15 (good, 2.92 h)	89.6° 16:05	10.65	1%	84.4°
2046-02-05 Mon	73	—	unknown	19:20–22:10 (good, 2.83 h)	89.5° 16:05	10.62	0%	73.9°
2046-02-06 Tue	71	—	unknown	19:20–22:10 (good, 2.83 h)	89.7° 16:00	10.58	1%	63.7°
2046-02-07 Wed	68	—	unknown	19:20–22:05 (good, 2.75 h)	89.8° 15:55	10.54	4%	53.8°
2046-02-08 Thu	64	—	unknown	19:20–22:00 (good, 2.67 h)	89.8° 15:50	10.51	8%	44.6°
2046-02-09 Fri	57	—	unknown	19:25–21:55 (good, 2.5 h)	89.6° 15:45	10.47	14%	36.6°
2046-02-10 Sat	48	—	unknown	19:25–21:40 (good, 2.25 h)	89.6° 15:45	10.43	21%	30.6°
2046-02-11 Sun	39	—	unknown	19:25–21:30 (good, 2.08 h)	89.8° 15:40	10.4	29%	28.3°
2046-02-12 Mon	31	—	unknown	19:25–21:15 (good, 1.83 h)	89.8° 15:35	10.36	38%	30.4°
2046-02-13 Tue	24	—	unknown	18:55–22:10 (marginal, 3.25 h)	89.7° 15:30	10.32	48%	36.6°
2046-02-14 Wed	20	—	unknown	19:30–22:00 (marginal, 2.5 h)	89.5° 15:25	10.28	58%	45.4°
2046-02-15 Thu	17	—	unknown	19:30–21:50 (marginal, 2.33 h)	89.7° 15:25	10.24	68%	55.8°
2046-02-16 Fri	17	—	unknown	19:30–21:45 (marginal, 2.25 h)	89.8° 15:20	10.2	78%	67.3°
2046-02-17 Sat	19	—	unknown	19:30–21:45 (marginal, 2.25 h)	89.8° 15:15	10.16	87%	79.7°
2046-02-18 Sun	22	—	unknown	19:35–20:00 (good, 0.42 h)	89.6° 15:10	10.12	94%	92.6°
2046-02-19 Mon	27	—	unknown	19:35–20:50 (good, 1.25 h)	89.5° 15:10	10.08	98%	105.8°
2046-02-20 Tue	32	—	unknown	19:35–21:00 (good, 1.42 h)	89.7° 15:05	10.03	100%	118.8°
2046-02-21 Wed	32	—	unknown	19:35–20:55 (good, 1.33 h)	89.8° 15:00	9.99	98%	131.2°
2046-02-22 Thu	35	—	unknown	19:40–20:55 (good, 1.25 h)	89.8° 14:55	9.95	94%	142.1°
2046-02-23 Fri	35	—	unknown	19:40–21:00 (good, 1.33 h)	89.6° 14:50	9.91	87%	149.7°
2046-02-24 Sat	33	—	unknown	19:40–20:55 (good, 1.25 h)	89.6° 14:50	9.86	78%	151.6°
2046-02-25 Sun	32	—	unknown	19:40–20:55 (good, 1.25 h)	89.8° 14:45	9.82	68%	147.3°
2046-02-26 Mon	29	—	unknown	19:45–20:50 (good, 1.08 h)	89.8° 14:40	9.77	58%	139.3°
2046-02-27 Tue	28	—	unknown	19:45–20:45 (good, 1.0 h)	89.7° 14:35	9.73	47%	129.5°
2046-02-28 Wed	26	—	unknown	19:45–20:40 (good, 0.92 h)	89.5° 14:30	9.69	37%	119.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2046-01-30&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.