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: 04-04 (100), 04-05 (100), 04-06 (100), 04-07 (100), 04-08 (100) — by astronomy; check the weather when the night is within four days.

2043-03-18astronomy score per night — click a bar for that night2043-04-16

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-03-18 Wed	92	—	unknown	01:25–04:55 (good, 3.5 h)	87.1° 07:15	8.83	60%	112.8°
2043-03-19 Thu	89	—	unknown	01:25–04:55 (good, 3.5 h)	87.1° 07:10	8.78	70%	112.9°
2043-03-20 Fri	87	—	unknown	01:25–04:50 (good, 3.42 h)	87.1° 07:05	8.73	79%	111.7°
2043-03-21 Sat	75	—	unknown	01:25–04:50 (good, 3.42 h)	87.1° 07:00	8.68	87%	109.3°
2043-03-22 Sun	71	—	unknown	01:25–04:50 (good, 3.42 h)	87.1° 06:55	8.62	93%	106.0°
2043-03-23 Mon	65	—	unknown	01:30–04:45 (good, 3.25 h)	87.1° 06:55	8.57	97%	102.1°
2043-03-24 Tue	61	—	unknown	01:45–04:45 (good, 3.0 h)	87.1° 06:50	8.52	100%	97.7°
2043-03-25 Wed	57	—	unknown	02:00–04:45 (good, 2.75 h)	87.1° 06:45	8.47	100%	93.1°
2043-03-26 Thu	54	—	unknown	02:10–04:40 (good, 2.5 h)	87.1° 06:40	8.41	98%	88.4°
2043-03-27 Fri	53	—	unknown	02:10–04:40 (good, 2.5 h)	87.1° 06:35	8.36	95%	83.8°
2043-03-28 Sat	53	—	unknown	01:55–05:35 (good, 2.67 h)	87.1° 07:35	8.31	90%	79.4°
2043-03-29 Sun	55	—	unknown	02:15–05:35 (good, 3.33 h)	87.1° 07:30	8.25	84%	75.5°
2043-03-30 Mon	60	—	unknown	01:55–05:35 (good, 3.67 h)	87.1° 07:25	8.2	76%	72.1°
2043-03-31 Tue	70	—	unknown	01:25–05:30 (good, 4.08 h)	87.1° 07:20	8.14	68%	69.5°
2043-04-01 Wed	83	—	unknown	01:25–05:30 (good, 4.08 h)	87.1° 07:20	8.09	58%	67.7°
2043-04-02 Thu	94	—	unknown	01:20–05:30 (good, 4.17 h)	87.1° 07:15	8.03	49%	67.0°
2043-04-03 Fri	99	—	unknown	01:15–05:25 (good, 4.17 h)	87.1° 07:10	7.98	38%	67.4°
2043-04-04 Sat	100	—	unknown	01:10–05:25 (good, 4.25 h)	87.1° 07:05	7.92	29%	69.0°
2043-04-05 Sun	100	—	unknown	01:10–05:20 (good, 4.17 h)	87.1° 07:00	7.87	19%	71.8°
2043-04-06 Mon	100	—	unknown	01:05–05:20 (good, 4.25 h)	87.1° 07:00	7.81	11%	75.7°
2043-04-07 Tue	100	—	unknown	01:00–05:20 (good, 4.33 h)	87.1° 06:55	7.76	5%	80.6°
2043-04-08 Wed	100	—	unknown	00:55–05:15 (good, 4.33 h)	87.1° 06:50	7.7	1%	86.1°
2043-04-09 Thu	100	—	unknown	00:50–05:15 (good, 4.42 h)	87.1° 06:45	7.64	0%	92.0°
2043-04-10 Fri	100	—	unknown	00:50–05:10 (good, 4.33 h)	87.1° 06:40	7.59	2%	97.8°
2043-04-11 Sat	100	—	unknown	00:45–05:10 (good, 4.42 h)	87.1° 06:40	7.53	7%	103.1°
2043-04-12 Sun	100	—	unknown	00:40–05:10 (good, 4.5 h)	87.1° 06:35	7.47	14%	107.5°
2043-04-13 Mon	100	—	unknown	00:40–05:05 (good, 4.42 h)	87.1° 06:30	7.41	23%	110.7°
2043-04-14 Tue	100	—	unknown	00:35–05:05 (good, 4.5 h)	87.1° 06:25	7.36	34%	112.6°
2043-04-15 Wed	100	—	unknown	00:35–05:00 (good, 4.42 h)	87.1° 06:25	7.3	45%	113.0°
2043-04-16 Thu	100	—	unknown	00:35–05:00 (good, 4.42 h)	87.1° 06:20	7.24	55%	112.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-03-18&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.