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: 01-17 (100), 01-18 (96), 01-19 (89), 02-02 (87), 02-03 (86) — by astronomy; check the weather when the night is within four days.

2048-01-17astronomy score per night — click a bar for that night2048-02-15

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2048-01-17 Fri	100	—	unknown	19:00–23:45 (good, 4.75 h)	79.2° 18:10	11.19	8%	63.9°
2048-01-18 Sat	96	—	unknown	19:00–23:40 (good, 4.67 h)	79.2° 18:05	11.16	14%	51.2°
2048-01-19 Sun	89	—	unknown	19:00–23:35 (good, 4.58 h)	79.2° 18:05	11.14	22%	39.1°
2048-01-20 Mon	80	—	unknown	19:00–23:30 (good, 4.5 h)	79.2° 18:00	11.12	31%	28.0°
2048-01-21 Tue	63	—	unknown	19:00–23:05 (good, 4.08 h)	79.2° 17:55	11.09	41%	18.8°
2048-01-22 Wed	48	—	unknown	19:05–21:50 (good, 2.75 h)	79.2° 17:50	11.06	50%	14.7°
2048-01-23 Thu	36	—	unknown	19:05–23:40 (marginal, 4.58 h)	79.2° 17:45	11.04	60%	18.9°
2048-01-24 Fri	25	—	unknown	19:05–23:25 (marginal, 4.33 h)	79.2° 17:45	11.01	69%	27.8°
2048-01-25 Sat	22	—	unknown	19:05–23:10 (marginal, 4.08 h)	79.2° 17:40	10.98	77%	38.3°
2048-01-26 Sun	23	—	unknown	19:05–23:05 (marginal, 4.0 h)	79.2° 17:35	10.95	84%	49.4°
2048-01-27 Mon	27	—	unknown	19:10–23:00 (marginal, 3.83 h)	79.2° 17:30	10.92	91%	60.9°
2048-01-28 Tue	35	—	unknown	19:10–19:25 (good, 0.25 h)	79.2° 17:25	10.89	96%	72.7°
2048-01-29 Wed	45	—	unknown	19:10–20:45 (good, 1.58 h)	79.2° 17:25	10.86	99%	84.9°
2048-01-30 Thu	57	—	unknown	19:10–21:55 (good, 2.75 h)	79.2° 17:20	10.83	100%	97.2°
2048-01-31 Fri	68	—	unknown	19:15–22:30 (good, 3.25 h)	79.2° 17:15	10.8	99%	109.8°
2048-02-01 Sat	85	—	unknown	19:15–22:35 (good, 3.33 h)	79.2° 17:10	10.77	96%	122.5°
2048-02-02 Sun	87	—	unknown	19:15–22:30 (good, 3.25 h)	79.2° 17:10	10.74	90%	135.2°
2048-02-03 Mon	86	—	unknown	19:15–22:30 (good, 3.25 h)	79.2° 17:05	10.7	83%	147.6°
2048-02-04 Tue	86	—	unknown	19:15–22:30 (good, 3.25 h)	79.2° 17:00	10.67	74%	158.8°
2048-02-05 Wed	83	—	unknown	19:20–22:30 (good, 3.17 h)	79.2° 16:55	10.63	63%	165.2°
2048-02-06 Thu	81	—	unknown	19:20–22:25 (good, 3.08 h)	79.2° 16:50	10.6	52%	160.7°
2048-02-07 Fri	78	—	unknown	19:20–22:20 (good, 3.0 h)	79.2° 16:50	10.56	41%	149.7°
2048-02-08 Sat	76	—	unknown	19:20–22:15 (good, 2.92 h)	79.2° 16:45	10.53	30%	136.9°
2048-02-09 Sun	72	—	unknown	19:25–22:15 (good, 2.83 h)	79.2° 16:40	10.49	20%	123.5°
2048-02-10 Mon	71	—	unknown	19:25–22:10 (good, 2.75 h)	79.2° 16:35	10.45	12%	109.9°
2048-02-11 Tue	68	—	unknown	19:25–22:05 (good, 2.67 h)	79.2° 16:30	10.41	5%	96.2°
2048-02-12 Wed	66	—	unknown	19:25–22:00 (good, 2.58 h)	79.2° 16:30	10.38	2%	82.6°
2048-02-13 Thu	64	—	unknown	19:25–21:55 (good, 2.5 h)	79.2° 16:25	10.34	0%	69.3°
2048-02-14 Fri	60	—	unknown	19:30–21:55 (good, 2.42 h)	79.2° 16:20	10.3	1%	56.3°
2048-02-15 Sat	58	—	unknown	19:30–21:50 (good, 2.33 h)	79.2° 16:15	10.26	4%	43.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2048-01-17&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.