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 HD 189733: 12-02 (54), 12-03 (52), 12-04 (50), 12-05 (49), 12-06 (48) — by astronomy; check the weather when the night is within four days.

2029-12-02astronomy score per night — click a bar for that night2029-12-31

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-12-02 Sun	54	—	unknown	18:35–20:45 (good, 2.17 h)	71.1° 15:35	11.35	11%	96.9°
2029-12-03 Mon	52	—	unknown	18:35–20:40 (good, 2.08 h)	71.1° 15:30	11.37	4%	85.1°
2029-12-04 Tue	50	—	unknown	18:35–20:35 (good, 2.0 h)	71.1° 15:30	11.38	1%	73.5°
2029-12-05 Wed	49	—	unknown	18:35–20:30 (good, 1.92 h)	71.1° 15:25	11.4	0%	62.4°
2029-12-06 Thu	48	—	unknown	18:35–20:25 (good, 1.83 h)	71.1° 15:20	11.41	2%	52.4°
2029-12-07 Fri	45	—	unknown	18:35–20:25 (good, 1.83 h)	71.1° 15:15	11.42	7%	44.5°
2029-12-08 Sat	39	—	unknown	18:35–20:20 (good, 1.75 h)	71.1° 15:15	11.44	14%	39.6°
2029-12-09 Sun	33	—	unknown	18:35–20:05 (good, 1.5 h)	71.1° 15:10	11.45	23%	38.6°
2029-12-10 Mon	28	—	unknown	18:35–19:55 (good, 1.33 h)	71.1° 15:05	11.46	32%	41.3°
2029-12-11 Tue	23	—	unknown	18:35–19:45 (good, 1.17 h)	71.1° 15:00	11.47	42%	46.8°
2029-12-12 Wed	20	—	unknown	18:35–19:05 (good, 0.5 h)	71.1° 14:55	11.47	52%	54.0°
2029-12-13 Thu	17	—	unknown	18:35–20:20 (marginal, 1.75 h)	71.1° 14:55	11.48	61%	62.2°
2029-12-14 Fri	16	—	unknown	18:35–20:15 (marginal, 1.67 h)	71.1° 14:50	11.49	70%	70.9°
2029-12-15 Sat	16	—	unknown	18:35–20:10 (marginal, 1.58 h)	71.1° 14:45	11.49	79%	80.0°
2029-12-16 Sun	16	—	unknown	18:35–18:45 (good, 0.17 h)	71.1° 14:40	11.5	86%	89.2°
2029-12-17 Mon	17	—	unknown	18:35–19:10 (good, 0.58 h)	71.1° 14:35	11.5	92%	98.5°
2029-12-18 Tue	19	—	unknown	18:35–19:20 (good, 0.75 h)	71.1° 14:35	11.5	96%	107.7°
2029-12-19 Wed	21	—	unknown	18:35–19:20 (good, 0.75 h)	71.1° 14:30	11.51	99%	116.6°
2029-12-20 Thu	21	—	unknown	18:35–19:20 (good, 0.75 h)	71.1° 14:25	11.51	100%	125.1°
2029-12-21 Fri	20	—	unknown	18:35–19:20 (good, 0.75 h)	71.1° 14:20	11.51	99%	132.5°
2029-12-22 Sat	22	—	unknown	18:35–19:15 (good, 0.67 h)	71.1° 14:20	11.51	96%	138.2°
2029-12-23 Sun	21	—	unknown	18:40–19:20 (good, 0.67 h)	71.1° 14:15	11.51	91%	141.3°
2029-12-24 Mon	20	—	unknown	18:40–19:15 (good, 0.58 h)	71.1° 14:10	11.5	84%	140.8°
2029-12-25 Tue	19	—	unknown	18:40–19:10 (good, 0.5 h)	71.1° 14:05	11.5	76%	136.9°
2029-12-26 Wed	17	—	unknown	18:40–19:10 (good, 0.5 h)	71.1° 14:00	11.49	66%	130.1°
2029-12-27 Thu	15	—	unknown	18:40–19:05 (good, 0.42 h)	71.1° 14:00	11.49	55%	121.4°
2029-12-28 Fri	14	—	unknown	18:40–19:00 (good, 0.33 h)	71.1° 13:55	11.48	44%	111.4°
2029-12-29 Sat	12	—	unknown	18:40–18:55 (good, 0.25 h)	71.1° 13:50	11.48	33%	100.6°
2029-12-30 Sun	11	—	unknown	18:40–18:50 (good, 0.17 h)	71.1° 13:45	11.47	23%	89.3°
2029-12-31 Mon	8	—	unknown	18:45–18:50 (good, 0.08 h)	71.1° 13:40	11.46	14%	78.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-12-02&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.