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: 04-08 (100), 04-09 (100), 04-10 (100), 04-11 (100), 04-12 (100) — by astronomy; check the weather when the night is within four days.

2029-03-23astronomy score per night — click a bar for that night2029-04-21

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-03-23 Fri	98	—	unknown	01:05–04:45 (good, 3.67 h)	87.1° 06:50	8.55	56%	118.3°
2029-03-24 Sat	98	—	unknown	01:00–05:45 (good, 3.75 h)	87.1° 07:45	8.5	67%	119.1°
2029-03-25 Sun	96	—	unknown	02:00–05:40 (good, 3.67 h)	87.1° 07:45	8.45	77%	118.3°
2029-03-26 Mon	93	—	unknown	02:00–05:40 (good, 3.67 h)	87.1° 07:40	8.39	86%	115.5°
2029-03-27 Tue	80	—	unknown	02:00–05:40 (good, 3.67 h)	87.1° 07:35	8.34	93%	111.1°
2029-03-28 Wed	73	—	unknown	02:00–05:35 (good, 3.58 h)	87.1° 07:30	8.28	98%	105.2°
2029-03-29 Thu	66	—	unknown	02:10–05:35 (good, 3.42 h)	87.1° 07:30	8.23	100%	98.3°
2029-03-30 Fri	60	—	unknown	02:30–05:35 (good, 3.08 h)	87.1° 07:25	8.18	99%	90.9°
2029-03-31 Sat	56	—	unknown	02:40–05:30 (good, 2.83 h)	87.1° 07:20	8.12	95%	83.6°
2029-04-01 Sun	55	—	unknown	02:25–05:30 (good, 3.08 h)	87.1° 07:15	8.07	88%	76.7°
2029-04-02 Mon	57	—	unknown	01:45–05:25 (good, 3.67 h)	87.1° 07:10	8.01	80%	70.7°
2029-04-03 Tue	65	—	unknown	01:15–05:25 (good, 4.17 h)	87.1° 07:10	7.96	70%	65.9°
2029-04-04 Wed	81	—	unknown	01:10–05:25 (good, 4.25 h)	87.1° 07:05	7.9	59%	62.6°
2029-04-05 Thu	91	—	unknown	01:05–05:20 (good, 4.25 h)	87.1° 07:00	7.85	49%	61.0°
2029-04-06 Fri	95	—	unknown	01:00–05:20 (good, 4.33 h)	87.1° 06:55	7.79	39%	60.9°
2029-04-07 Sat	99	—	unknown	01:00–05:15 (good, 4.25 h)	87.1° 06:50	7.73	29%	62.4°
2029-04-08 Sun	100	—	unknown	00:55–05:15 (good, 4.33 h)	87.1° 06:50	7.68	21%	65.2°
2029-04-09 Mon	100	—	unknown	00:50–05:15 (good, 4.42 h)	87.1° 06:45	7.62	14%	69.0°
2029-04-10 Tue	100	—	unknown	00:45–05:10 (good, 4.42 h)	87.1° 06:40	7.56	8%	73.6°
2029-04-11 Wed	100	—	unknown	00:40–05:10 (good, 4.5 h)	87.1° 06:35	7.51	4%	78.8°
2029-04-12 Thu	100	—	unknown	00:40–05:05 (good, 4.42 h)	87.1° 06:35	7.45	1%	84.4°
2029-04-13 Fri	100	—	unknown	00:35–05:05 (good, 4.5 h)	87.1° 06:30	7.39	0%	90.1°
2029-04-14 Sat	100	—	unknown	00:30–05:05 (good, 4.58 h)	87.1° 06:25	7.33	1%	95.9°
2029-04-15 Sun	100	—	unknown	00:25–05:00 (good, 4.58 h)	87.1° 06:20	7.28	4%	101.5°
2029-04-16 Mon	100	—	unknown	00:25–05:00 (good, 4.58 h)	87.1° 06:15	7.22	8%	106.8°
2029-04-17 Tue	100	—	unknown	00:20–05:00 (good, 4.67 h)	87.1° 06:15	7.16	14%	111.5°
2029-04-18 Wed	100	—	unknown	00:15–04:55 (good, 4.67 h)	87.1° 06:10	7.1	22%	115.3°
2029-04-19 Thu	100	—	unknown	00:15–04:55 (good, 4.67 h)	87.1° 06:05	7.05	31%	118.0°
2029-04-20 Fri	100	—	unknown	00:10–04:50 (good, 4.67 h)	87.1° 06:00	6.99	40%	119.3°
2029-04-21 Sat	100	—	unknown	00:10–04:50 (good, 4.67 h)	87.1° 05:55	6.93	51%	119.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-03-23&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.