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 North America Nebula: 01-02 (50), 01-03 (50), 01-04 (49), 01-05 (47), 01-06 (44) — by astronomy; check the weather when the night is within four days.

2028-12-24astronomy score per night — click a bar for that night2029-01-22

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2028-12-24 Sun	32	—	unknown	18:40–19:35 (good, 0.92 h)	87.2° 15:05	11.5	60%	59.1°
2028-12-25 Mon	29	—	unknown	18:40–18:45 (good, 0.08 h)	87.2° 15:05	11.5	69%	64.0°
2028-12-26 Tue	26	—	unknown	18:40–21:40 (marginal, 3.0 h)	87.2° 15:00	11.49	77%	70.0°
2028-12-27 Wed	26	—	unknown	18:40–21:35 (marginal, 2.92 h)	87.2° 14:55	11.49	85%	76.8°
2028-12-28 Thu	28	—	unknown	18:40–19:00 (good, 0.33 h)	87.2° 14:50	11.48	92%	84.2°
2028-12-29 Fri	30	—	unknown	18:40–19:35 (good, 0.92 h)	87.2° 14:45	11.47	96%	91.9°
2028-12-30 Sat	35	—	unknown	18:40–20:20 (good, 1.67 h)	87.2° 14:45	11.47	99%	99.9°
2028-12-31 Sun	38	—	unknown	18:45–20:35 (good, 1.83 h)	87.2° 14:40	11.46	100%	107.6°
2029-01-01 Mon	43	—	unknown	18:45–20:40 (good, 1.92 h)	87.2° 14:35	11.45	98%	114.7°
2029-01-02 Tue	50	—	unknown	18:45–20:40 (good, 1.92 h)	87.2° 14:30	11.44	94%	120.7°
2029-01-03 Wed	50	—	unknown	18:45–20:40 (good, 1.92 h)	87.2° 14:25	11.42	87%	125.0°
2029-01-04 Thu	49	—	unknown	18:45–20:45 (good, 2.0 h)	87.2° 14:25	11.41	78%	126.9°
2029-01-05 Fri	47	—	unknown	18:45–20:40 (good, 1.92 h)	87.2° 14:20	11.4	68%	126.2°
2029-01-06 Sat	44	—	unknown	18:50–20:35 (good, 1.75 h)	87.2° 14:15	11.38	57%	123.0°
2029-01-07 Sun	43	—	unknown	18:50–20:30 (good, 1.67 h)	87.2° 14:10	11.37	46%	117.7°
2029-01-08 Mon	42	—	unknown	18:50–20:30 (good, 1.67 h)	87.2° 14:10	11.35	35%	111.1°
2029-01-09 Tue	40	—	unknown	18:50–20:25 (good, 1.58 h)	87.2° 14:05	11.34	24%	103.5°
2029-01-10 Wed	38	—	unknown	18:50–20:20 (good, 1.5 h)	87.2° 14:00	11.32	16%	95.5°
2029-01-11 Thu	36	—	unknown	18:55–20:15 (good, 1.33 h)	87.2° 13:55	11.3	8%	87.3°
2029-01-12 Fri	34	—	unknown	18:55–20:10 (good, 1.25 h)	87.2° 13:50	11.28	4%	79.4°
2029-01-13 Sat	33	—	unknown	18:55–20:10 (good, 1.25 h)	87.2° 13:50	11.26	1%	71.9°
2029-01-14 Sun	32	—	unknown	18:55–20:05 (good, 1.17 h)	87.2° 13:45	11.24	0%	65.3°
2029-01-15 Mon	30	—	unknown	18:55–20:00 (good, 1.08 h)	87.2° 13:40	11.22	2%	59.8°
2029-01-16 Tue	28	—	unknown	18:55–19:55 (good, 1.0 h)	87.2° 13:35	11.2	5%	55.8°
2029-01-17 Wed	24	—	unknown	19:00–19:50 (good, 0.83 h)	87.2° 13:30	11.17	10%	53.5°
2029-01-18 Thu	22	—	unknown	19:00–19:40 (good, 0.67 h)	87.2° 13:30	11.15	17%	53.1°
2029-01-19 Fri	19	—	unknown	19:00–19:30 (good, 0.5 h)	87.2° 13:25	11.13	24%	54.6°
2029-01-20 Sat	17	—	unknown	19:00–19:20 (good, 0.33 h)	87.2° 13:20	11.1	33%	57.7°
2029-01-21 Sun	13	—	unknown	19:05–19:10 (good, 0.08 h)	87.2° 13:15	11.08	42%	62.2°
2029-01-22 Mon	12	—	unknown	19:05–20:10 (marginal, 1.08 h)	87.2° 13:15	11.05	51%	67.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2028-12-24&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.