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: 02-05 (69), 02-06 (69), 02-07 (68), 02-08 (67), 02-04 (63) — by astronomy; check the weather when the night is within four days.

2034-01-28astronomy score per night — click a bar for that night2034-02-26

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-01-28 Sat	31	—	unknown	19:10–23:05 (marginal, 3.92 h)	89.7° 16:35	10.88	68%	48.1°
2034-01-29 Sun	29	—	unknown	19:10–22:55 (marginal, 3.75 h)	89.8° 16:30	10.85	78%	57.7°
2034-01-30 Mon	30	—	unknown	19:10–22:50 (marginal, 3.67 h)	89.7° 16:25	10.82	86%	68.3°
2034-01-31 Tue	34	—	unknown	19:15–19:45 (good, 0.5 h)	89.5° 16:20	10.79	93%	79.2°
2034-02-01 Wed	41	—	unknown	19:15–20:45 (good, 1.5 h)	89.6° 16:20	10.76	97%	90.2°
2034-02-02 Thu	49	—	unknown	19:15–21:45 (good, 2.5 h)	89.7° 16:15	10.72	100%	101.1°
2034-02-03 Fri	57	—	unknown	19:15–22:00 (good, 2.75 h)	89.8° 16:10	10.69	100%	111.5°
2034-02-04 Sat	63	—	unknown	19:20–22:00 (good, 2.67 h)	89.6° 16:05	10.65	98%	121.3°
2034-02-05 Sun	69	—	unknown	19:20–22:00 (good, 2.67 h)	89.5° 16:00	10.62	94%	130.1°
2034-02-06 Mon	69	—	unknown	19:20–22:00 (good, 2.67 h)	89.6° 16:00	10.58	88%	137.4°
2034-02-07 Tue	68	—	unknown	19:20–22:05 (good, 2.75 h)	89.8° 15:55	10.55	81%	142.5°
2034-02-08 Wed	67	—	unknown	19:20–22:00 (good, 2.67 h)	89.7° 15:50	10.51	73%	144.7°
2034-02-09 Thu	63	—	unknown	19:25–21:55 (good, 2.5 h)	89.6° 15:45	10.47	64%	143.4°
2034-02-10 Fri	62	—	unknown	19:25–21:50 (good, 2.42 h)	89.5° 15:45	10.44	55%	139.1°
2034-02-11 Sat	59	—	unknown	19:25–21:50 (good, 2.42 h)	89.7° 15:40	10.4	46%	132.6°
2034-02-12 Sun	57	—	unknown	19:25–21:45 (good, 2.33 h)	89.8° 15:35	10.36	36%	124.5°
2034-02-13 Mon	54	—	unknown	19:30–21:40 (good, 2.17 h)	89.7° 15:30	10.32	27%	115.3°
2034-02-14 Tue	53	—	unknown	19:30–21:35 (good, 2.08 h)	89.5° 15:25	10.28	18%	105.4°
2034-02-15 Wed	50	—	unknown	19:30–21:30 (good, 2.0 h)	89.6° 15:25	10.24	11%	94.9°
2034-02-16 Thu	48	—	unknown	19:30–21:30 (good, 2.0 h)	89.7° 15:20	10.2	5%	84.0°
2034-02-17 Fri	46	—	unknown	19:30–21:25 (good, 1.92 h)	89.8° 15:15	10.16	2%	72.8°
2034-02-18 Sat	44	—	unknown	19:35–21:20 (good, 1.75 h)	89.7° 15:10	10.12	0%	61.9°
2034-02-19 Sun	43	—	unknown	19:35–21:15 (good, 1.67 h)	89.5° 15:05	10.08	1%	51.5°
2034-02-20 Mon	39	—	unknown	19:35–21:10 (good, 1.58 h)	89.6° 15:05	10.04	5%	42.7°
2034-02-21 Tue	35	—	unknown	19:35–21:05 (good, 1.5 h)	89.7° 15:00	10.0	12%	36.9°
2034-02-22 Wed	29	—	unknown	19:40–20:55 (good, 1.25 h)	89.7° 14:55	9.95	20%	35.5°
2034-02-23 Thu	24	—	unknown	19:40–20:40 (good, 1.0 h)	89.6° 14:50	9.91	30%	39.1°
2034-02-24 Fri	19	—	unknown	19:40–20:25 (good, 0.75 h)	89.5° 14:50	9.87	42%	46.3°
2034-02-25 Sat	15	—	unknown	19:40–21:25 (marginal, 1.75 h)	89.7° 14:45	9.82	53%	55.6°
2034-02-26 Sun	13	—	unknown	19:45–21:15 (marginal, 1.5 h)	89.8° 14:40	9.78	64%	65.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-01-28&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.