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: 08-10 (100), 08-11 (100), 08-12 (100), 08-13 (100), 08-14 (100) — by astronomy; check the weather when the night is within four days.

2045-07-18astronomy score per night — click a bar for that night2045-08-16

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2045-07-18 Tue	65	—	unknown	01:40–04:05 (good, 2.42 h)	79.2° 07:10	5.15	27%	142.9°
2045-07-19 Wed	66	—	unknown	01:35–04:05 (good, 2.5 h)	79.2° 07:05	5.2	38%	155.1°
2045-07-20 Thu	70	—	unknown	01:35–04:10 (good, 2.58 h)	79.2° 07:00	5.24	48%	164.1°
2045-07-21 Fri	72	—	unknown	01:30–04:10 (good, 2.67 h)	79.2° 06:55	5.29	59%	164.3°
2045-07-22 Sat	74	—	unknown	01:25–04:10 (good, 2.75 h)	79.2° 06:50	5.34	69%	156.1°
2045-07-23 Sun	77	—	unknown	01:25–04:10 (good, 2.75 h)	79.2° 06:50	5.39	78%	145.3°
2045-07-24 Mon	78	—	unknown	01:25–04:15 (good, 2.83 h)	79.2° 06:45	5.44	86%	133.8°
2045-07-25 Tue	78	—	unknown	01:20–04:15 (good, 2.92 h)	79.2° 06:40	5.49	92%	122.2°
2045-07-26 Wed	67	—	unknown	01:25–04:15 (good, 2.83 h)	79.2° 06:35	5.55	96%	110.6°
2045-07-27 Thu	59	—	unknown	01:30–04:20 (good, 2.83 h)	79.2° 06:35	5.6	99%	99.1°
2045-07-28 Fri	49	—	unknown	02:00–04:20 (good, 2.33 h)	79.2° 06:30	5.65	100%	87.5°
2045-07-29 Sat	40	—	unknown	03:10–04:20 (good, 1.17 h)	79.2° 06:25	5.71	99%	76.1°
2045-07-30 Sun	32	—	unknown	00:40–04:25 (marginal, 3.75 h)	79.2° 06:20	5.76	96%	64.7°
2045-07-31 Mon	26	—	unknown	00:40–04:25 (marginal, 3.75 h)	79.2° 06:15	5.81	92%	53.3°
2045-08-01 Tue	23	—	unknown	00:35–04:25 (marginal, 3.83 h)	79.2° 06:15	5.87	86%	42.1°
2045-08-02 Wed	22	—	unknown	00:30–04:30 (marginal, 4.0 h)	79.2° 06:10	5.93	79%	31.2°
2045-08-03 Thu	28	—	unknown	00:20–04:30 (marginal, 4.17 h)	79.2° 06:05	5.98	70%	21.2°
2045-08-04 Fri	37	—	unknown	00:05–04:30 (marginal, 4.42 h)	79.2° 06:00	6.04	61%	14.7°
2045-08-05 Sat	50	—	unknown	00:55–04:35 (good, 3.67 h)	79.2° 05:55	6.09	51%	17.1°
2045-08-06 Sun	65	—	unknown	00:45–04:35 (good, 3.83 h)	79.2° 05:55	6.15	40%	26.5°
2045-08-07 Mon	83	—	unknown	00:20–04:35 (good, 4.25 h)	79.2° 05:50	6.21	30%	38.4°
2045-08-08 Tue	92	—	unknown	00:20–04:35 (good, 4.25 h)	79.2° 05:45	6.26	20%	51.5°
2045-08-09 Wed	98	—	unknown	00:15–04:40 (good, 4.42 h)	79.2° 05:40	6.32	11%	65.3°
2045-08-10 Thu	100	—	unknown	00:10–04:40 (good, 4.5 h)	79.2° 05:40	6.38	5%	79.6°
2045-08-11 Fri	100	—	unknown	00:05–04:40 (good, 4.58 h)	79.2° 05:35	6.44	1%	94.3°
2045-08-12 Sat	100	—	unknown	00:00–04:45 (good, 4.75 h)	79.2° 05:30	6.49	0%	109.0°
2045-08-13 Sun	100	—	unknown	00:00–04:45 (good, 4.75 h)	79.2° 05:25	6.55	2%	123.6°
2045-08-14 Mon	100	—	unknown	23:55–04:45 (good, 4.83 h)	79.2° 05:20	6.61	7%	137.8°
2045-08-15 Tue	100	—	unknown	23:50–04:50 (good, 5.0 h)	79.2° 05:20	6.67	14%	151.0°
2045-08-16 Wed	100	—	unknown	23:45–04:50 (good, 5.08 h)	79.2° 05:15	6.72	24%	161.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2045-07-18&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.