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: 03-15 (93), 03-14 (92), 03-13 (91), 03-12 (90), 03-11 (84) — by astronomy; check the weather when the night is within four days.

2037-02-14astronomy score per night — click a bar for that night2037-03-15

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2037-02-14 Sat	60	—	unknown	03:20–05:45 (good, 2.42 h)	87.1° 09:15	10.27	0%	69.6°
2037-02-15 Sun	61	—	unknown	03:20–05:45 (good, 2.42 h)	87.1° 09:15	10.23	0%	74.6°
2037-02-16 Mon	63	—	unknown	03:15–05:45 (good, 2.5 h)	87.1° 09:10	10.19	3%	80.2°
2037-02-17 Tue	63	—	unknown	03:10–05:40 (good, 2.5 h)	87.1° 09:05	10.15	7%	86.1°
2037-02-18 Wed	65	—	unknown	03:05–05:40 (good, 2.58 h)	87.1° 09:00	10.11	12%	92.1°
2037-02-19 Thu	66	—	unknown	03:05–05:40 (good, 2.58 h)	87.1° 08:55	10.07	19%	98.2°
2037-02-20 Fri	68	—	unknown	03:00–05:40 (good, 2.67 h)	87.1° 08:55	10.03	27%	104.0°
2037-02-21 Sat	68	—	unknown	02:55–05:35 (good, 2.67 h)	87.1° 08:50	9.98	36%	109.4°
2037-02-22 Sun	69	—	unknown	02:50–05:35 (good, 2.75 h)	87.1° 08:45	9.94	46%	114.2°
2037-02-23 Mon	71	—	unknown	02:45–05:35 (good, 2.83 h)	87.1° 08:40	9.9	57%	117.9°
2037-02-24 Tue	71	—	unknown	02:50–05:30 (good, 2.67 h)	87.1° 08:35	9.86	68%	120.1°
2037-02-25 Wed	71	—	unknown	02:45–05:30 (good, 2.75 h)	87.1° 08:35	9.81	78%	120.5°
2037-02-26 Thu	69	—	unknown	02:45–05:30 (good, 2.75 h)	87.1° 08:30	9.77	86%	118.9°
2037-02-27 Fri	59	—	unknown	02:45–05:25 (good, 2.67 h)	87.1° 08:25	9.72	94%	115.2°
2037-02-28 Sat	55	—	unknown	02:50–05:25 (good, 2.58 h)	87.1° 08:20	9.68	98%	109.7°
2037-03-01 Sun	49	—	unknown	02:55–05:25 (good, 2.5 h)	87.1° 08:20	9.63	100%	103.0°
2037-03-02 Mon	44	—	unknown	03:20–05:25 (good, 2.08 h)	87.1° 08:15	9.59	99%	95.6°
2037-03-03 Tue	40	—	unknown	03:45–05:20 (good, 1.58 h)	87.1° 08:10	9.54	94%	88.0°
2037-03-04 Wed	39	—	unknown	03:55–05:20 (good, 1.42 h)	87.1° 08:05	9.49	88%	80.6°
2037-03-05 Thu	40	—	unknown	03:35–05:20 (good, 1.75 h)	87.1° 08:00	9.45	79%	73.9°
2037-03-06 Fri	44	—	unknown	02:45–05:15 (good, 2.5 h)	87.1° 08:00	9.4	69%	68.2°
2037-03-07 Sat	49	—	unknown	02:25–05:15 (good, 2.83 h)	87.1° 07:55	9.35	59%	63.8°
2037-03-08 Sun	58	—	unknown	02:10–05:15 (good, 3.08 h)	87.1° 07:50	9.3	49%	60.9°
2037-03-09 Mon	67	—	unknown	01:50–05:10 (good, 3.33 h)	87.1° 07:45	9.26	39%	59.5°
2037-03-10 Tue	75	—	unknown	01:50–05:10 (good, 3.33 h)	87.1° 07:40	9.21	29%	59.8°
2037-03-11 Wed	84	—	unknown	01:45–05:10 (good, 3.42 h)	87.1° 07:40	9.16	21%	61.4°
2037-03-12 Thu	90	—	unknown	01:40–05:05 (good, 3.42 h)	87.1° 07:35	9.11	14%	64.4°
2037-03-13 Fri	91	—	unknown	01:35–05:05 (good, 3.5 h)	87.1° 07:30	9.06	8%	68.4°
2037-03-14 Sat	92	—	unknown	01:30–05:05 (good, 3.58 h)	87.1° 07:25	9.01	4%	73.3°
2037-03-15 Sun	93	—	unknown	01:30–05:00 (good, 3.5 h)	87.1° 07:25	8.96	1%	78.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2037-02-14&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.