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: 02-12 (57), 02-13 (54), 02-14 (53), 02-15 (50), 02-16 (48) — by astronomy; check the weather when the night is within four days.

2034-02-12astronomy score per night — click a bar for that night2034-03-13

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
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°
2034-02-27 Mon	13	—	unknown	19:45–21:10 (marginal, 1.42 h)	89.7° 14:35	9.73	74%	76.6°
2034-02-28 Tue	13	—	unknown	19:45–21:10 (marginal, 1.42 h)	89.5° 14:30	9.69	83%	87.4°
2034-03-01 Wed	14	—	unknown	19:45–20:00 (good, 0.25 h)	89.6° 14:30	9.64	90%	98.0°
2034-03-02 Thu	15	—	unknown	19:45–20:10 (good, 0.42 h)	89.7° 14:25	9.6	95%	108.4°
2034-03-03 Fri	16	—	unknown	19:50–20:15 (good, 0.42 h)	89.8° 14:20	9.55	99%	118.3°
2034-03-04 Sat	16	—	unknown	19:50–20:15 (good, 0.42 h)	89.7° 14:15	9.51	100%	127.3°
2034-03-05 Sun	15	—	unknown	19:50–20:10 (good, 0.33 h)	89.5° 14:10	9.46	99%	135.1°
2034-03-06 Mon	15	—	unknown	19:50–20:10 (good, 0.33 h)	89.6° 14:10	9.41	97%	141.0°
2034-03-07 Tue	13	—	unknown	19:55–20:15 (good, 0.33 h)	89.7° 14:05	9.36	93%	144.2°
2034-03-08 Wed	12	—	unknown	19:55–20:10 (good, 0.25 h)	89.7° 14:00	9.32	87%	144.1°
2034-03-09 Thu	11	—	unknown	19:55–20:05 (good, 0.17 h)	89.6° 13:55	9.27	80%	140.7°
2034-03-10 Fri	9	—	unknown	19:55–20:00 (good, 0.08 h)	89.5° 13:55	9.22	72%	134.8°
2034-03-11 Sat	7	—	unknown	19:25–20:30 (marginal, 1.08 h)	89.7° 13:50	9.17	63%	127.2°
2034-03-12 Sun	6	—	unknown	20:00–20:25 (marginal, 0.42 h)	89.8° 13:45	9.12	53%	118.5°
2034-03-13 Mon	5	—	unknown	20:00–20:25 (marginal, 0.42 h)	89.7° 13:40	9.07	44%	109.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-02-12&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.