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: 02-19 (46), 02-20 (45), 02-21 (45), 02-22 (42), 02-18 (41) — by astronomy; check the weather when the night is within four days.

2030-02-12astronomy score per night — click a bar for that night2030-03-13

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2030-02-12 Tue	19	—	unknown	19:25–22:05 (marginal, 2.67 h)	79.1° 16:25	10.36	72%	50.5°
2030-02-13 Wed	19	—	unknown	19:30–22:05 (marginal, 2.58 h)	79.1° 16:20	10.32	81%	62.1°
2030-02-14 Thu	22	—	unknown	19:30–22:05 (marginal, 2.58 h)	79.1° 16:20	10.28	88%	74.1°
2030-02-15 Fri	26	—	unknown	19:30–20:00 (good, 0.5 h)	79.1° 16:15	10.24	94%	86.4°
2030-02-16 Sat	32	—	unknown	19:30–21:00 (good, 1.5 h)	79.1° 16:10	10.2	98%	99.2°
2030-02-17 Sun	38	—	unknown	19:30–21:20 (good, 1.83 h)	79.1° 16:05	10.16	100%	112.2°
2030-02-18 Mon	41	—	unknown	19:35–21:25 (good, 1.83 h)	79.1° 16:00	10.12	99%	125.3°
2030-02-19 Tue	46	—	unknown	19:35–21:20 (good, 1.75 h)	79.1° 16:00	10.08	96%	138.4°
2030-02-20 Wed	45	—	unknown	19:35–21:20 (good, 1.75 h)	79.1° 15:55	10.04	91%	151.0°
2030-02-21 Thu	45	—	unknown	19:35–21:25 (good, 1.83 h)	79.1° 15:50	10.0	83%	161.3°
2030-02-22 Fri	42	—	unknown	19:40–21:20 (good, 1.67 h)	79.1° 15:45	9.95	74%	164.1°
2030-02-23 Sat	41	—	unknown	19:40–21:15 (good, 1.58 h)	79.1° 15:45	9.91	63%	156.4°
2030-02-24 Sun	38	—	unknown	19:40–21:10 (good, 1.5 h)	79.1° 15:40	9.87	52%	144.6°
2030-02-25 Mon	37	—	unknown	19:40–21:05 (good, 1.42 h)	79.1° 15:35	9.82	40%	131.8°
2030-02-26 Tue	34	—	unknown	19:45–21:05 (good, 1.33 h)	79.1° 15:30	9.78	30%	118.6°
2030-02-27 Wed	33	—	unknown	19:45–21:00 (good, 1.25 h)	79.1° 15:25	9.74	20%	105.5°
2030-02-28 Thu	31	—	unknown	19:45–20:55 (good, 1.17 h)	79.1° 15:25	9.69	12%	92.4°
2030-03-01 Fri	29	—	unknown	19:45–20:50 (good, 1.08 h)	79.1° 15:20	9.65	6%	79.4°
2030-03-02 Sat	27	—	unknown	19:45–20:45 (good, 1.0 h)	79.1° 15:15	9.6	2%	66.7°
2030-03-03 Sun	25	—	unknown	19:50–20:45 (good, 0.92 h)	79.1° 15:10	9.55	0%	54.4°
2030-03-04 Mon	24	—	unknown	19:50–20:40 (good, 0.83 h)	79.1° 15:05	9.51	1%	42.4°
2030-03-05 Tue	22	—	unknown	19:50–20:35 (good, 0.75 h)	79.1° 15:05	9.46	3%	31.3°
2030-03-06 Wed	20	—	unknown	19:50–20:30 (good, 0.67 h)	79.1° 15:00	9.41	7%	21.6°
2030-03-07 Thu	16	—	unknown	19:55–20:20 (good, 0.42 h)	79.1° 14:55	9.37	13%	15.9°
2030-03-08 Fri	14	—	unknown	19:55–20:15 (good, 0.33 h)	79.1° 14:50	9.32	20%	17.9°
2030-03-09 Sat	10	—	unknown	19:55–20:00 (good, 0.08 h)	79.1° 14:50	9.27	28%	25.8°
2030-03-10 Sun	8	—	unknown	19:55–20:45 (marginal, 0.83 h)	79.1° 14:45	9.22	37%	35.8°
2030-03-11 Mon	6	—	unknown	20:00–20:40 (marginal, 0.67 h)	79.1° 14:40	9.17	46%	46.6°
2030-03-12 Tue	4	—	unknown	20:00–20:30 (marginal, 0.5 h)	79.1° 14:35	9.12	56%	57.9°
2030-03-13 Wed	4	—	unknown	20:00–20:25 (marginal, 0.42 h)	79.1° 14:30	9.07	65%	69.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2030-02-12&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.