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: 03-14 (91), 03-12 (90), 03-13 (90), 03-11 (89), 03-10 (88) — by astronomy; check the weather when the night is within four days.

2038-02-13astronomy score per night — click a bar for that night2038-03-14

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2038-02-13 Sat	58	—	unknown	03:25–05:45 (good, 2.33 h)	87.1° 09:20	10.32	65%	116.5°
2038-02-14 Sun	59	—	unknown	03:30–05:45 (good, 2.25 h)	87.1° 09:20	10.28	74%	118.5°
2038-02-15 Mon	58	—	unknown	03:30–05:45 (good, 2.25 h)	87.1° 09:15	10.24	83%	119.0°
2038-02-16 Tue	57	—	unknown	03:25–05:45 (good, 2.33 h)	87.1° 09:10	10.2	90%	117.8°
2038-02-17 Wed	49	—	unknown	03:25–05:40 (good, 2.25 h)	87.1° 09:05	10.16	96%	114.8°
2038-02-18 Thu	46	—	unknown	03:30–05:40 (good, 2.17 h)	87.1° 09:00	10.12	99%	110.2°
2038-02-19 Fri	42	—	unknown	03:30–05:40 (good, 2.17 h)	87.1° 09:00	10.08	100%	104.4°
2038-02-20 Sat	38	—	unknown	03:50–05:40 (good, 1.83 h)	87.1° 08:55	10.04	98%	97.6°
2038-02-21 Sun	35	—	unknown	04:10–05:35 (good, 1.42 h)	87.1° 08:50	10.0	92%	90.5°
2038-02-22 Mon	35	—	unknown	04:15–05:35 (good, 1.33 h)	87.1° 08:45	9.95	85%	83.3°
2038-02-23 Tue	36	—	unknown	03:55–05:35 (good, 1.67 h)	87.1° 08:40	9.91	76%	76.6°
2038-02-24 Wed	40	—	unknown	03:15–05:30 (good, 2.25 h)	87.1° 08:40	9.87	65%	70.8°
2038-02-25 Thu	45	—	unknown	03:00–05:30 (good, 2.5 h)	87.1° 08:35	9.82	54%	66.1°
2038-02-26 Fri	53	—	unknown	02:50–05:30 (good, 2.67 h)	87.1° 08:30	9.78	43%	62.8°
2038-02-27 Sat	62	—	unknown	02:30–05:30 (good, 3.0 h)	87.1° 08:25	9.73	32%	61.2°
2038-02-28 Sun	68	—	unknown	02:30–05:25 (good, 2.92 h)	87.1° 08:25	9.69	23%	61.3°
2038-03-01 Mon	75	—	unknown	02:25–05:25 (good, 3.0 h)	87.1° 08:20	9.64	15%	62.9°
2038-03-02 Tue	79	—	unknown	02:20–05:25 (good, 3.08 h)	87.1° 08:15	9.6	9%	65.8°
2038-03-03 Wed	79	—	unknown	02:15–05:20 (good, 3.08 h)	87.1° 08:10	9.55	4%	69.9°
2038-03-04 Thu	81	—	unknown	02:15–05:20 (good, 3.08 h)	87.1° 08:05	9.5	1%	74.7°
2038-03-05 Fri	83	—	unknown	02:10–05:20 (good, 3.17 h)	87.1° 08:05	9.46	0%	80.1°
2038-03-06 Sat	83	—	unknown	02:05–05:15 (good, 3.17 h)	87.1° 08:00	9.41	1%	85.7°
2038-03-07 Sun	84	—	unknown	02:00–05:15 (good, 3.25 h)	87.1° 07:55	9.36	4%	91.5°
2038-03-08 Mon	86	—	unknown	01:55–05:15 (good, 3.33 h)	87.1° 07:50	9.32	8%	97.1°
2038-03-09 Tue	87	—	unknown	01:55–05:10 (good, 3.25 h)	87.1° 07:45	9.27	14%	102.5°
2038-03-10 Wed	88	—	unknown	01:50–05:10 (good, 3.33 h)	87.1° 07:45	9.22	21%	107.5°
2038-03-11 Thu	89	—	unknown	01:45–05:10 (good, 3.42 h)	87.1° 07:40	9.17	29%	111.8°
2038-03-12 Fri	90	—	unknown	01:40–05:05 (good, 3.42 h)	87.1° 07:35	9.12	38%	115.3°
2038-03-13 Sat	90	—	unknown	01:35–05:05 (good, 3.5 h)	87.1° 07:30	9.07	48%	117.8°
2038-03-14 Sun	91	—	unknown	01:40–05:05 (good, 3.42 h)	87.1° 07:30	9.02	58%	118.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2038-02-13&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.