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 North America Nebula: 07-25 (100), 07-26 (100), 07-27 (100), 07-28 (100), 07-29 (100) — by astronomy; check the weather when the night is within four days.

2036-07-25astronomy score per night — click a bar for that night2036-08-23

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-07-25 Fri	100	—	unknown	22:45–04:15 (good, 5.5 h)	87.2° 02:05	5.5	9%	120.5°
2036-07-26 Sat	100	—	unknown	22:45–04:15 (good, 5.5 h)	87.2° 02:00	5.56	17%	118.3°
2036-07-27 Sun	100	—	unknown	22:40–04:20 (good, 5.67 h)	87.2° 01:55	5.61	27%	114.3°
2036-07-28 Mon	100	—	unknown	22:40–04:20 (good, 5.67 h)	87.2° 01:50	5.66	37%	109.0°
2036-07-29 Tue	100	—	unknown	22:40–04:20 (good, 5.67 h)	87.2° 01:50	5.72	48%	103.1°
2036-07-30 Wed	100	—	unknown	22:35–04:25 (good, 5.83 h)	87.2° 01:45	5.77	58%	96.7°
2036-07-31 Thu	100	—	unknown	22:35–04:25 (good, 5.83 h)	87.2° 01:40	5.82	68%	90.3°
2036-08-01 Fri	100	—	unknown	22:35–04:25 (good, 5.83 h)	87.2° 01:35	5.88	77%	83.9°
2036-08-02 Sat	100	—	unknown	22:30–04:30 (good, 6.0 h)	87.2° 01:35	5.94	85%	77.9°
2036-08-03 Sun	100	—	unknown	22:30–04:30 (good, 6.0 h)	87.2° 01:30	5.99	91%	72.4°
2036-08-04 Mon	73	—	unknown	22:30–04:30 (good, 6.0 h)	87.2° 01:25	6.05	96%	67.6°
2036-08-05 Tue	66	—	unknown	01:55–04:35 (good, 2.67 h)	87.2° 01:20	6.1	99%	63.7°
2036-08-06 Wed	61	—	unknown	03:50–04:35 (good, 0.75 h)	87.2° 01:15	6.16	100%	60.9°
2036-08-07 Thu	63	—	unknown	22:25–23:15 (good, 0.83 h)	87.2° 01:15	6.22	99%	59.4°
2036-08-08 Fri	66	—	unknown	22:20–23:50 (good, 1.5 h)	87.2° 01:10	6.27	97%	59.3°
2036-08-09 Sat	71	—	unknown	22:20–00:55 (good, 2.58 h)	87.2° 01:05	6.33	93%	60.7°
2036-08-10 Sun	100	—	unknown	22:15–02:35 (good, 4.33 h)	87.2° 01:00	6.39	87%	63.5°
2036-08-11 Mon	100	—	unknown	22:15–04:20 (good, 6.08 h)	87.2° 00:55	6.45	80%	67.5°
2036-08-12 Tue	100	—	unknown	22:15–04:45 (good, 6.5 h)	87.2° 00:55	6.5	71%	72.5°
2036-08-13 Wed	100	—	unknown	22:10–04:45 (good, 6.58 h)	87.2° 00:50	6.56	62%	78.3°
2036-08-14 Thu	100	—	unknown	22:10–04:45 (good, 6.58 h)	87.2° 00:45	6.62	51%	84.8°
2036-08-15 Fri	100	—	unknown	22:10–04:50 (good, 6.67 h)	87.2° 00:40	6.68	41%	91.6°
2036-08-16 Sat	100	—	unknown	22:05–04:50 (good, 6.75 h)	87.2° 00:40	6.73	30%	98.6°
2036-08-17 Sun	100	—	unknown	22:05–04:50 (good, 6.75 h)	87.2° 00:35	6.79	20%	105.4°
2036-08-18 Mon	100	—	unknown	22:00–04:55 (good, 6.92 h)	87.2° 00:30	6.85	11%	111.5°
2036-08-19 Tue	100	—	unknown	22:00–04:55 (good, 6.92 h)	87.2° 00:25	6.91	5%	116.6°
2036-08-20 Wed	100	—	unknown	22:00–04:55 (good, 6.92 h)	87.2° 00:20	6.96	1%	119.8°
2036-08-21 Thu	100	—	unknown	21:55–04:55 (good, 7.0 h)	87.2° 00:20	7.02	0%	120.9°
2036-08-22 Fri	100	—	unknown	21:55–05:00 (good, 7.08 h)	87.2° 00:15	7.08	2%	119.5°
2036-08-23 Sat	100	—	unknown	21:50–05:00 (good, 7.17 h)	87.2° 00:10	7.13	7%	116.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-07-25&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.