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 HD 189733: 07-27 (100), 07-28 (100), 07-29 (100), 07-30 (100), 07-31 (100) — by astronomy; check the weather when the night is within four days.

2032-07-20astronomy score per night — click a bar for that night2032-08-18

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2032-07-20 Tue	58	—	unknown	02:35–04:10 (good, 1.58 h)	71.1° 01:25	5.25	95%	49.5°
2032-07-21 Wed	41	—	unknown	22:50–04:10 (marginal, 5.33 h)	71.1° 01:20	5.3	99%	41.8°
2032-07-22 Thu	33	—	unknown	22:50–04:10 (marginal, 5.33 h)	71.1° 01:20	5.35	100%	37.6°
2032-07-23 Fri	36	—	unknown	22:50–04:10 (marginal, 5.33 h)	71.1° 01:15	5.4	98%	38.2°
2032-07-24 Sat	48	—	unknown	22:45–04:15 (marginal, 5.5 h)	71.1° 01:10	5.45	93%	43.5°
2032-07-25 Sun	65	—	unknown	22:45–00:55 (good, 2.17 h)	71.1° 01:05	5.5	86%	52.0°
2032-07-26 Mon	98	—	unknown	22:45–03:35 (good, 4.83 h)	71.1° 01:05	5.55	76%	62.1°
2032-07-27 Tue	100	—	unknown	22:40–04:20 (good, 5.67 h)	71.1° 01:00	5.61	66%	72.9°
2032-07-28 Wed	100	—	unknown	22:40–04:20 (good, 5.67 h)	71.1° 00:55	5.66	55%	83.7°
2032-07-29 Thu	100	—	unknown	22:40–04:20 (good, 5.67 h)	71.1° 00:50	5.71	44%	94.5°
2032-07-30 Fri	100	—	unknown	22:35–04:25 (good, 5.83 h)	71.1° 00:45	5.77	34%	104.8°
2032-07-31 Sat	100	—	unknown	22:35–04:25 (good, 5.83 h)	71.1° 00:45	5.82	25%	114.6°
2032-08-01 Sun	100	—	unknown	22:35–04:25 (good, 5.83 h)	71.1° 00:40	5.88	16%	123.6°
2032-08-02 Mon	100	—	unknown	22:30–04:30 (good, 6.0 h)	71.1° 00:35	5.93	10%	131.6°
2032-08-03 Tue	100	—	unknown	22:30–04:30 (good, 6.0 h)	71.1° 00:30	5.99	5%	137.9°
2032-08-04 Wed	100	—	unknown	22:30–04:30 (good, 6.0 h)	71.1° 00:25	6.05	2%	141.8°
2032-08-05 Thu	100	—	unknown	22:25–04:35 (good, 6.17 h)	71.1° 00:25	6.1	0%	142.7°
2032-08-06 Fri	100	—	unknown	22:25–04:35 (good, 6.17 h)	71.1° 00:20	6.16	1%	140.5°
2032-08-07 Sat	100	—	unknown	22:25–04:35 (good, 6.17 h)	71.1° 00:15	6.22	3%	135.6°
2032-08-08 Sun	100	—	unknown	22:20–04:35 (good, 6.25 h)	71.1° 00:10	6.27	7%	128.9°
2032-08-09 Mon	100	—	unknown	22:20–04:40 (good, 6.33 h)	71.1° 00:10	6.33	12%	120.9°
2032-08-10 Tue	100	—	unknown	22:15–04:40 (good, 6.42 h)	71.1° 00:05	6.39	19%	112.1°
2032-08-11 Wed	100	—	unknown	22:15–04:40 (good, 6.42 h)	71.1° 00:00	6.44	27%	102.7°
2032-08-12 Thu	100	—	unknown	22:15–04:45 (good, 6.5 h)	71.1° 23:55	6.5	36%	93.0°
2032-08-13 Fri	100	—	unknown	22:10–04:45 (good, 6.58 h)	71.1° 23:50	6.56	46%	83.0°
2032-08-14 Sat	100	—	unknown	22:10–04:45 (good, 6.58 h)	71.1° 23:50	6.62	56%	72.9°
2032-08-15 Sun	100	—	unknown	22:10–04:50 (good, 6.67 h)	71.1° 23:45	6.67	67%	62.8°
2032-08-16 Mon	96	—	unknown	22:05–04:45 (good, 6.67 h)	71.1° 23:40	6.73	77%	53.1°
2032-08-17 Tue	87	—	unknown	00:50–04:40 (good, 3.83 h)	71.1° 23:35	6.79	86%	44.7°
2032-08-18 Wed	63	—	unknown	04:25–04:40 (good, 0.25 h)	71.1° 23:30	6.85	93%	38.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2032-07-20&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.