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: 03-24 (40), 04-06 (40), 03-23 (39), 03-25 (39), 03-26 (39) — by astronomy; check the weather when the night is within four days.

2048-03-08astronomy score per night — click a bar for that night2048-04-06

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2048-03-08 Sun	20	—	unknown	04:25–05:10 (good, 0.75 h)	71.2° 09:15	9.29	34%	49.9°
2048-03-09 Mon	24	—	unknown	04:15–05:10 (good, 0.92 h)	71.2° 09:10	9.24	23%	43.2°
2048-03-10 Tue	28	—	unknown	04:05–05:10 (good, 1.08 h)	71.2° 09:05	9.19	15%	39.6°
2048-03-11 Wed	29	—	unknown	04:00–05:05 (good, 1.08 h)	71.2° 09:00	9.14	8%	39.7°
2048-03-12 Thu	30	—	unknown	03:55–05:05 (good, 1.17 h)	71.1° 08:55	9.09	3%	43.5°
2048-03-13 Fri	31	—	unknown	03:50–05:05 (good, 1.25 h)	71.2° 08:55	9.04	1%	49.9°
2048-03-14 Sat	32	—	unknown	03:50–05:00 (good, 1.17 h)	71.2° 08:50	8.99	0%	58.0°
2048-03-15 Sun	33	—	unknown	03:45–05:00 (good, 1.25 h)	71.2° 08:45	8.94	2%	66.8°
2048-03-16 Mon	34	—	unknown	03:40–05:00 (good, 1.33 h)	71.2° 08:40	8.89	6%	76.1°
2048-03-17 Tue	34	—	unknown	03:35–04:55 (good, 1.33 h)	71.1° 08:40	8.84	11%	85.5°
2048-03-18 Wed	36	—	unknown	03:35–04:55 (good, 1.33 h)	71.2° 08:35	8.79	18%	94.8°
2048-03-19 Thu	37	—	unknown	03:30–04:55 (good, 1.42 h)	71.2° 08:30	8.74	25%	104.0°
2048-03-20 Fri	37	—	unknown	03:25–04:50 (good, 1.42 h)	71.2° 08:25	8.69	34%	112.8°
2048-03-21 Sat	37	—	unknown	03:20–04:50 (good, 1.5 h)	71.1° 08:20	8.64	43%	121.2°
2048-03-22 Sun	38	—	unknown	03:15–04:45 (good, 1.5 h)	71.1° 08:20	8.58	52%	128.8°
2048-03-23 Mon	39	—	unknown	03:15–04:45 (good, 1.5 h)	71.2° 08:15	8.53	62%	135.1°
2048-03-24 Tue	40	—	unknown	03:15–04:45 (good, 1.5 h)	71.2° 08:10	8.48	71%	139.5°
2048-03-25 Wed	39	—	unknown	03:10–04:40 (good, 1.5 h)	71.2° 08:05	8.42	80%	140.9°
2048-03-26 Thu	39	—	unknown	03:10–04:40 (good, 1.5 h)	71.1° 08:00	8.37	88%	138.9°
2048-03-27 Fri	36	—	unknown	03:05–04:40 (good, 1.58 h)	71.2° 08:00	8.32	94%	133.5°
2048-03-28 Sat	36	—	unknown	04:05–05:35 (good, 1.5 h)	71.2° 08:55	8.26	98%	125.6°
2048-03-29 Sun	35	—	unknown	04:00–05:35 (good, 1.58 h)	71.2° 08:50	8.21	100%	115.9°
2048-03-30 Mon	30	—	unknown	04:05–05:30 (good, 1.42 h)	71.2° 08:45	8.15	99%	105.2°
2048-03-31 Tue	27	—	unknown	04:05–05:30 (good, 1.42 h)	71.1° 08:45	8.1	95%	93.9°
2048-04-01 Wed	26	—	unknown	04:25–05:30 (good, 1.08 h)	71.2° 08:40	8.05	89%	82.5°
2048-04-02 Thu	24	—	unknown	04:30–05:25 (good, 0.92 h)	71.2° 08:35	7.99	80%	71.3°
2048-04-03 Fri	26	—	unknown	04:15–05:25 (good, 1.17 h)	71.2° 08:30	7.93	70%	60.8°
2048-04-04 Sat	27	—	unknown	03:50–05:20 (good, 1.5 h)	71.1° 08:25	7.88	59%	51.6°
2048-04-05 Sun	32	—	unknown	03:40–05:20 (good, 1.67 h)	71.1° 08:25	7.82	48%	44.3°
2048-04-06 Mon	40	—	unknown	03:20–05:20 (good, 2.0 h)	71.2° 08:20	7.77	37%	39.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2048-03-08&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.