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 (100), 08-03 (100), 08-04 (100), 08-05 (100), 08-06 (100) — by astronomy; check the weather when the night is within four days.

2046-07-22astronomy score per night — click a bar for that night2046-08-20

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2046-07-22 Sun	20	—	unknown	01:15–04:10 (marginal, 2.92 h)	79.2° 06:55	5.33	79%	40.1°
2046-07-23 Mon	21	—	unknown	01:05–04:10 (marginal, 3.08 h)	79.2° 06:50	5.38	70%	29.5°
2046-07-24 Tue	28	—	unknown	00:55–04:15 (marginal, 3.33 h)	79.2° 06:45	5.43	62%	20.0°
2046-07-25 Wed	36	—	unknown	02:35–04:15 (good, 1.67 h)	79.2° 06:40	5.48	52%	14.3°
2046-07-26 Thu	46	—	unknown	01:30–04:15 (good, 2.75 h)	79.2° 06:40	5.53	42%	17.1°
2046-07-27 Fri	59	—	unknown	01:20–04:20 (good, 3.0 h)	79.2° 06:35	5.59	33%	26.1°
2046-07-28 Sat	72	—	unknown	01:00–04:20 (good, 3.33 h)	79.2° 06:30	5.64	23%	37.3°
2046-07-29 Sun	83	—	unknown	01:00–04:20 (good, 3.33 h)	79.2° 06:25	5.69	15%	49.5°
2046-07-30 Mon	91	—	unknown	00:55–04:25 (good, 3.5 h)	79.2° 06:20	5.75	8%	62.4°
2046-07-31 Tue	97	—	unknown	00:50–04:25 (good, 3.58 h)	79.2° 06:20	5.8	3%	75.9°
2046-08-01 Wed	98	—	unknown	00:45–04:25 (good, 3.67 h)	79.2° 06:15	5.86	0%	89.8°
2046-08-02 Thu	100	—	unknown	00:45–04:25 (good, 3.67 h)	79.2° 06:10	5.91	0%	104.0°
2046-08-03 Fri	100	—	unknown	00:40–04:30 (good, 3.83 h)	79.2° 06:05	5.97	3%	118.3°
2046-08-04 Sat	100	—	unknown	00:35–04:30 (good, 3.92 h)	79.2° 06:00	6.02	9%	132.4°
2046-08-05 Sun	100	—	unknown	00:30–04:30 (good, 4.0 h)	79.2° 06:00	6.08	17%	146.1°
2046-08-06 Mon	100	—	unknown	00:25–04:35 (good, 4.17 h)	79.2° 05:55	6.14	27%	158.3°
2046-08-07 Tue	100	—	unknown	00:25–04:35 (good, 4.17 h)	79.2° 05:50	6.19	37%	165.7°
2046-08-08 Wed	100	—	unknown	00:20–04:35 (good, 4.25 h)	79.2° 05:45	6.25	49%	161.7°
2046-08-09 Thu	100	—	unknown	00:15–04:40 (good, 4.42 h)	79.2° 05:45	6.31	60%	151.2°
2046-08-10 Fri	100	—	unknown	00:15–04:40 (good, 4.42 h)	79.2° 05:40	6.36	70%	139.1°
2046-08-11 Sat	100	—	unknown	00:15–04:40 (good, 4.42 h)	79.2° 05:35	6.42	79%	126.7°
2046-08-12 Sun	100	—	unknown	00:15–04:45 (good, 4.5 h)	79.2° 05:30	6.48	87%	114.3°
2046-08-13 Mon	100	—	unknown	00:20–04:45 (good, 4.42 h)	79.2° 05:25	6.54	93%	102.0°
2046-08-14 Tue	80	—	unknown	00:40–04:45 (good, 4.08 h)	79.2° 05:25	6.59	97%	89.9°
2046-08-15 Wed	63	—	unknown	01:55–04:50 (good, 2.92 h)	79.2° 05:20	6.65	100%	78.0°
2046-08-16 Thu	48	—	unknown	04:05–04:50 (good, 0.75 h)	79.2° 05:15	6.71	100%	66.2°
2046-08-17 Fri	36	—	unknown	23:35–04:50 (marginal, 5.25 h)	79.2° 05:10	6.77	98%	54.7°
2046-08-18 Sat	26	—	unknown	23:40–04:50 (marginal, 5.17 h)	79.2° 05:05	6.82	95%	43.4°
2046-08-19 Sun	21	—	unknown	23:35–04:55 (marginal, 5.33 h)	79.2° 05:05	6.88	90%	32.6°
2046-08-20 Mon	25	—	unknown	23:25–04:55 (marginal, 5.5 h)	79.2° 05:00	6.94	84%	22.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2046-07-22&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.