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: 04-07 (100), 04-08 (100), 04-09 (100), 04-10 (100), 04-11 (100) — by astronomy; check the weather when the night is within four days.

2048-03-19astronomy score per night — click a bar for that night2048-04-17

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2048-03-19 Thu	97	—	unknown	01:10–04:55 (good, 3.75 h)	87.1° 07:05	8.74	25%	107.1°
2048-03-20 Fri	98	—	unknown	01:10–04:50 (good, 3.67 h)	87.1° 07:00	8.69	34%	111.7°
2048-03-21 Sat	98	—	unknown	01:10–04:50 (good, 3.67 h)	87.1° 07:00	8.64	43%	115.5°
2048-03-22 Sun	97	—	unknown	01:05–04:45 (good, 3.67 h)	87.1° 06:55	8.58	52%	118.2°
2048-03-23 Mon	97	—	unknown	01:05–04:45 (good, 3.67 h)	87.1° 06:50	8.53	62%	119.6°
2048-03-24 Tue	97	—	unknown	01:00–04:45 (good, 3.75 h)	87.1° 06:45	8.48	71%	119.6°
2048-03-25 Wed	95	—	unknown	01:00–04:40 (good, 3.67 h)	87.1° 06:40	8.42	80%	118.0°
2048-03-26 Thu	93	—	unknown	01:00–04:40 (good, 3.67 h)	87.1° 06:40	8.37	88%	114.9°
2048-03-27 Fri	79	—	unknown	01:00–04:40 (good, 3.67 h)	87.1° 06:35	8.32	94%	110.3°
2048-03-28 Sat	72	—	unknown	01:00–05:35 (good, 3.58 h)	87.1° 07:30	8.26	98%	104.5°
2048-03-29 Sun	66	—	unknown	02:10–05:35 (good, 3.42 h)	87.1° 07:25	8.21	100%	97.9°
2048-03-30 Mon	59	—	unknown	02:30–05:30 (good, 3.0 h)	87.1° 07:25	8.15	99%	90.8°
2048-03-31 Tue	56	—	unknown	02:45–05:30 (good, 2.75 h)	87.1° 07:20	8.1	95%	83.5°
2048-04-01 Wed	55	—	unknown	02:30–05:30 (good, 3.0 h)	87.1° 07:15	8.05	89%	76.5°
2048-04-02 Thu	56	—	unknown	01:45–05:25 (good, 3.67 h)	87.1° 07:10	7.99	80%	70.3°
2048-04-03 Fri	64	—	unknown	01:35–05:25 (good, 3.83 h)	87.1° 07:05	7.93	70%	65.3°
2048-04-04 Sat	80	—	unknown	01:10–05:20 (good, 4.17 h)	87.1° 07:05	7.88	59%	61.8°
2048-04-05 Sun	91	—	unknown	01:05–05:20 (good, 4.25 h)	87.1° 07:00	7.82	48%	60.2°
2048-04-06 Mon	96	—	unknown	01:00–05:20 (good, 4.33 h)	87.1° 06:55	7.77	37%	60.5°
2048-04-07 Tue	100	—	unknown	00:55–05:15 (good, 4.33 h)	87.1° 06:50	7.71	27%	62.5°
2048-04-08 Wed	100	—	unknown	00:55–05:15 (good, 4.33 h)	87.1° 06:45	7.65	18%	66.1°
2048-04-09 Thu	100	—	unknown	00:50–05:15 (good, 4.42 h)	87.1° 06:45	7.6	11%	70.8°
2048-04-10 Fri	100	—	unknown	00:45–05:10 (good, 4.42 h)	87.1° 06:40	7.54	5%	76.2°
2048-04-11 Sat	100	—	unknown	00:40–05:10 (good, 4.5 h)	87.1° 06:35	7.48	2%	82.1°
2048-04-12 Sun	100	—	unknown	00:35–05:05 (good, 4.5 h)	87.1° 06:30	7.43	0%	88.2°
2048-04-13 Mon	100	—	unknown	00:35–05:05 (good, 4.5 h)	87.1° 06:30	7.37	1%	94.3°
2048-04-14 Tue	100	—	unknown	00:30–05:05 (good, 4.58 h)	87.1° 06:25	7.31	3%	100.2°
2048-04-15 Wed	100	—	unknown	00:25–05:00 (good, 4.58 h)	87.1° 06:20	7.25	7%	105.7°
2048-04-16 Thu	100	—	unknown	00:20–05:00 (good, 4.67 h)	87.1° 06:15	7.2	12%	110.6°
2048-04-17 Fri	100	—	unknown	00:20–04:55 (good, 4.58 h)	87.1° 06:10	7.14	19%	114.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2048-03-19&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.