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 Vega: 11-27 (50), 11-28 (47), 11-29 (42), 11-30 (37), 12-01 (34) — by astronomy; check the weather when the night is within four days.

2038-11-27astronomy score per night — click a bar for that night2038-12-26

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2038-11-27 Sat	50	—	unknown	18:35–20:30 (good, 1.92 h)	87.1° 14:35	11.26	3%	63.1°
2038-11-28 Sun	47	—	unknown	18:35–20:30 (good, 1.92 h)	87.1° 14:30	11.28	8%	62.6°
2038-11-29 Mon	42	—	unknown	18:35–20:25 (good, 1.83 h)	87.1° 14:25	11.3	15%	64.0°
2038-11-30 Tue	37	—	unknown	18:35–20:15 (good, 1.67 h)	87.1° 14:20	11.31	24%	67.0°
2038-12-01 Wed	34	—	unknown	18:35–20:05 (good, 1.5 h)	87.1° 14:15	11.33	34%	71.1°
2038-12-02 Thu	30	—	unknown	18:35–19:55 (good, 1.33 h)	87.1° 14:15	11.35	44%	76.0°
2038-12-03 Fri	27	—	unknown	18:35–19:50 (good, 1.25 h)	87.1° 14:10	11.37	54%	81.3°
2038-12-04 Sat	24	—	unknown	18:35–19:40 (good, 1.08 h)	87.1° 14:05	11.38	64%	86.9°
2038-12-05 Sun	23	—	unknown	18:35–19:35 (good, 1.0 h)	87.1° 14:00	11.39	72%	92.4°
2038-12-06 Mon	22	—	unknown	18:35–19:30 (good, 0.92 h)	87.1° 14:00	11.41	80%	97.8°
2038-12-07 Tue	22	—	unknown	18:35–19:30 (good, 0.92 h)	87.1° 13:55	11.42	87%	102.9°
2038-12-08 Wed	22	—	unknown	18:35–19:25 (good, 0.83 h)	87.1° 13:50	11.43	93%	107.5°
2038-12-09 Thu	22	—	unknown	18:35–19:25 (good, 0.83 h)	87.1° 13:45	11.44	97%	111.5°
2038-12-10 Fri	22	—	unknown	18:35–19:25 (good, 0.83 h)	87.1° 13:40	11.45	99%	114.6°
2038-12-11 Sat	22	—	unknown	18:35–19:25 (good, 0.83 h)	87.1° 13:40	11.46	100%	116.6°
2038-12-12 Sun	22	—	unknown	18:35–19:20 (good, 0.75 h)	87.1° 13:35	11.47	99%	117.4°
2038-12-13 Mon	22	—	unknown	18:35–19:20 (good, 0.75 h)	87.1° 13:30	11.48	96%	116.9°
2038-12-14 Tue	24	—	unknown	18:35–19:20 (good, 0.75 h)	87.1° 13:25	11.49	90%	114.9°
2038-12-15 Wed	24	—	unknown	18:35–19:20 (good, 0.75 h)	87.1° 13:20	11.49	84%	111.8°
2038-12-16 Thu	23	—	unknown	18:35–19:20 (good, 0.75 h)	87.1° 13:20	11.5	75%	107.5°
2038-12-17 Fri	22	—	unknown	18:35–19:15 (good, 0.67 h)	87.1° 13:15	11.5	66%	102.3°
2038-12-18 Sat	20	—	unknown	18:35–19:10 (good, 0.58 h)	87.1° 13:10	11.5	55%	96.5°
2038-12-19 Sun	20	—	unknown	18:35–19:05 (good, 0.5 h)	87.1° 13:05	11.51	44%	90.2°
2038-12-20 Mon	18	—	unknown	18:35–19:00 (good, 0.42 h)	87.1° 13:05	11.51	33%	83.8°
2038-12-21 Tue	16	—	unknown	18:35–19:00 (good, 0.42 h)	87.1° 13:00	11.51	23%	77.5°
2038-12-22 Wed	15	—	unknown	18:35–18:55 (good, 0.33 h)	87.1° 12:55	11.51	14%	71.8°
2038-12-23 Thu	13	—	unknown	18:40–18:50 (good, 0.17 h)	87.1° 12:50	11.51	6%	67.2°
2038-12-24 Fri	12	—	unknown	18:40–18:45 (good, 0.08 h)	87.1° 12:45	11.5	2%	64.0°
2038-12-25 Sat	11	—	unknown	18:05–19:15 (marginal, 1.17 h)	87.1° 12:45	11.5	0%	62.6°
2038-12-26 Sun	11	—	unknown	18:05–19:10 (marginal, 1.08 h)	87.1° 12:40	11.5	1%	63.2°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2038-11-27&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.