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: 07-17 (100), 07-18 (100), 07-19 (100), 07-20 (100), 07-21 (100) — by astronomy; check the weather when the night is within four days.

2036-07-17astronomy score per night — click a bar for that night2036-08-15

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-07-17 Thu	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:15	5.11	36%	107.0°
2036-07-18 Fri	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:10	5.16	26%	112.6°
2036-07-19 Sat	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:05	5.2	17%	117.2°
2036-07-20 Sun	100	—	unknown	22:55–04:10 (good, 5.25 h)	87.1° 00:00	5.25	9%	120.3°
2036-07-21 Mon	100	—	unknown	22:50–04:10 (good, 5.33 h)	87.1° 00:00	5.3	3%	121.4°
2036-07-22 Tue	100	—	unknown	22:50–04:10 (good, 5.33 h)	87.1° 23:55	5.35	0%	120.1°
2036-07-23 Wed	100	—	unknown	22:50–04:10 (good, 5.33 h)	87.1° 23:50	5.4	0%	116.5°
2036-07-24 Thu	100	—	unknown	22:45–04:15 (good, 5.5 h)	87.1° 23:45	5.45	3%	111.1°
2036-07-25 Fri	100	—	unknown	22:45–04:15 (good, 5.5 h)	87.1° 23:45	5.5	9%	104.5°
2036-07-26 Sat	100	—	unknown	22:45–04:15 (good, 5.5 h)	87.1° 23:40	5.56	17%	97.3°
2036-07-27 Sun	100	—	unknown	22:40–04:20 (good, 5.67 h)	87.1° 23:35	5.61	27%	89.9°
2036-07-28 Mon	100	—	unknown	22:40–04:20 (good, 5.67 h)	87.1° 23:30	5.66	37%	82.8°
2036-07-29 Tue	100	—	unknown	22:40–04:20 (good, 5.67 h)	87.1° 23:25	5.72	48%	76.2°
2036-07-30 Wed	100	—	unknown	22:35–04:25 (good, 5.83 h)	87.1° 23:25	5.77	58%	70.3°
2036-07-31 Thu	100	—	unknown	22:35–04:25 (good, 5.83 h)	87.1° 23:20	5.82	68%	65.4°
2036-08-01 Fri	97	—	unknown	22:35–04:25 (good, 5.83 h)	87.1° 23:15	5.88	77%	61.8°
2036-08-02 Sat	91	—	unknown	22:30–04:30 (good, 6.0 h)	87.1° 23:10	5.94	85%	59.5°
2036-08-03 Sun	86	—	unknown	22:30–04:30 (good, 6.0 h)	87.1° 23:05	5.99	91%	58.6°
2036-08-04 Mon	61	—	unknown	01:20–02:10 (good, 0.83 h)	87.1° 23:05	6.05	96%	59.3°
2036-08-05 Tue	60	—	unknown	22:25–22:45 (good, 0.33 h)	87.1° 23:00	6.1	99%	61.5°
2036-08-06 Wed	62	—	unknown	22:25–23:40 (good, 1.25 h)	87.1° 22:55	6.16	100%	64.8°
2036-08-07 Thu	67	—	unknown	22:25–01:30 (good, 3.08 h)	87.1° 22:50	6.22	99%	69.2°
2036-08-08 Fri	73	—	unknown	22:20–02:05 (good, 3.75 h)	87.1° 22:50	6.27	97%	74.4°
2036-08-09 Sat	78	—	unknown	22:20–02:40 (good, 4.33 h)	87.1° 22:45	6.33	93%	80.2°
2036-08-10 Sun	100	—	unknown	22:15–03:25 (good, 5.17 h)	87.1° 22:40	6.39	87%	86.4°
2036-08-11 Mon	100	—	unknown	22:15–04:05 (good, 5.83 h)	87.1° 22:35	6.45	80%	92.7°
2036-08-12 Tue	100	—	unknown	22:15–04:10 (good, 5.92 h)	87.1° 22:30	6.5	71%	99.1°
2036-08-13 Wed	100	—	unknown	22:10–04:10 (good, 6.0 h)	87.1° 22:30	6.56	62%	105.2°
2036-08-14 Thu	100	—	unknown	22:10–04:15 (good, 6.08 h)	87.1° 22:25	6.62	51%	110.9°
2036-08-15 Fri	100	—	unknown	22:10–04:15 (good, 6.08 h)	87.1° 22:20	6.68	41%	115.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-07-17&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.