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 Triangulum Pinwheel: 08-02 (98), 08-17 (98), 08-01 (97), 07-31 (96), 08-03 (95) — by astronomy; check the weather when the night is within four days.

2036-07-19astronomy score per night — click a bar for that night2036-08-17

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-07-19 Sat	61	—	unknown	01:35–04:05 (good, 2.5 h)	79.1° 07:05	5.2	17%	43.1°
2036-07-20 Sun	69	—	unknown	01:30–04:10 (good, 2.67 h)	79.2° 07:00	5.25	9%	55.1°
2036-07-21 Mon	72	—	unknown	01:30–04:10 (good, 2.67 h)	79.2° 06:55	5.3	3%	68.1°
2036-07-22 Tue	74	—	unknown	01:25–04:10 (good, 2.75 h)	79.2° 06:50	5.35	0%	81.7°
2036-07-23 Wed	78	—	unknown	01:20–04:10 (good, 2.83 h)	79.1° 06:45	5.4	0%	95.5°
2036-07-24 Thu	81	—	unknown	01:15–04:15 (good, 3.0 h)	79.1° 06:45	5.45	3%	109.3°
2036-07-25 Fri	83	—	unknown	01:10–04:15 (good, 3.08 h)	79.2° 06:40	5.5	9%	122.6°
2036-07-26 Sat	85	—	unknown	01:10–04:15 (good, 3.08 h)	79.2° 06:35	5.56	17%	135.0°
2036-07-27 Sun	89	—	unknown	01:05–04:20 (good, 3.25 h)	79.1° 06:30	5.61	27%	145.7°
2036-07-28 Mon	91	—	unknown	01:00–04:20 (good, 3.33 h)	79.1° 06:25	5.66	37%	153.3°
2036-07-29 Tue	93	—	unknown	00:55–04:20 (good, 3.42 h)	79.1° 06:25	5.72	48%	155.4°
2036-07-30 Wed	94	—	unknown	00:55–04:25 (good, 3.5 h)	79.2° 06:20	5.77	58%	151.3°
2036-07-31 Thu	96	—	unknown	00:55–04:25 (good, 3.5 h)	79.2° 06:15	5.82	68%	143.4°
2036-08-01 Fri	97	—	unknown	00:50–04:25 (good, 3.58 h)	79.1° 06:10	5.88	77%	133.8°
2036-08-02 Sat	98	—	unknown	00:50–04:30 (good, 3.67 h)	79.1° 06:10	5.94	85%	123.5°
2036-08-03 Sun	95	—	unknown	00:50–04:30 (good, 3.67 h)	79.2° 06:05	5.99	91%	112.9°
2036-08-04 Mon	77	—	unknown	00:55–04:30 (good, 3.58 h)	79.2° 06:00	6.05	96%	102.2°
2036-08-05 Tue	66	—	unknown	01:10–04:35 (good, 3.42 h)	79.2° 05:55	6.1	99%	91.4°
2036-08-06 Wed	54	—	unknown	02:10–04:35 (good, 2.42 h)	79.1° 05:50	6.16	100%	80.6°
2036-08-07 Thu	44	—	unknown	03:20–04:35 (good, 1.25 h)	79.1° 05:50	6.22	99%	69.9°
2036-08-08 Fri	36	—	unknown	00:05–04:40 (marginal, 4.58 h)	79.2° 05:45	6.27	97%	59.4°
2036-08-09 Sat	30	—	unknown	00:00–04:40 (marginal, 4.67 h)	79.2° 05:40	6.33	93%	49.1°
2036-08-10 Sun	27	—	unknown	23:55–04:40 (marginal, 4.75 h)	79.2° 05:35	6.39	87%	39.5°
2036-08-11 Mon	28	—	unknown	23:50–04:40 (marginal, 4.83 h)	79.1° 05:30	6.45	80%	31.1°
2036-08-12 Tue	37	—	unknown	23:35–04:45 (marginal, 5.17 h)	79.1° 05:30	6.5	71%	25.5°
2036-08-13 Wed	49	—	unknown	02:05–03:25 (good, 1.33 h)	79.2° 05:25	6.56	62%	25.1°
2036-08-14 Thu	76	—	unknown	23:55–04:45 (good, 4.83 h)	79.2° 05:20	6.62	51%	30.3°
2036-08-15 Fri	85	—	unknown	23:50–04:50 (good, 5.0 h)	79.1° 05:15	6.68	41%	39.3°
2036-08-16 Sat	92	—	unknown	23:45–04:50 (good, 5.08 h)	79.1° 05:15	6.73	30%	50.4°
2036-08-17 Sun	98	—	unknown	23:40–04:50 (good, 5.17 h)	79.2° 05:10	6.79	20%	62.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-07-19&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.