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: 02-13 (60), 02-14 (59), 02-15 (58), 02-16 (57), 02-17 (55) — by astronomy; check the weather when the night is within four days.

2036-02-09astronomy score per night — click a bar for that night2036-03-09

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-02-09 Sat	30	—	unknown	19:25–19:50 (good, 0.42 h)	79.2° 16:40	10.49	94%	81.2°
2036-02-10 Sun	37	—	unknown	19:25–21:00 (good, 1.58 h)	79.1° 16:35	10.46	98%	95.0°
2036-02-11 Mon	47	—	unknown	19:25–21:45 (good, 2.33 h)	79.1° 16:30	10.42	100%	108.7°
2036-02-12 Tue	54	—	unknown	19:25–21:50 (good, 2.42 h)	79.1° 16:30	10.38	98%	122.1°
2036-02-13 Wed	60	—	unknown	19:25–21:45 (good, 2.33 h)	79.1° 16:25	10.34	94%	134.5°
2036-02-14 Thu	59	—	unknown	19:30–21:45 (good, 2.25 h)	79.2° 16:20	10.3	88%	145.4°
2036-02-15 Fri	58	—	unknown	19:30–21:50 (good, 2.33 h)	79.1° 16:15	10.26	80%	153.2°
2036-02-16 Sat	57	—	unknown	19:30–21:45 (good, 2.25 h)	79.1° 16:10	10.22	70%	155.7°
2036-02-17 Sun	55	—	unknown	19:30–21:40 (good, 2.17 h)	79.1° 16:10	10.18	60%	152.0°
2036-02-18 Mon	51	—	unknown	19:35–21:35 (good, 2.0 h)	79.2° 16:05	10.14	50%	144.4°
2036-02-19 Tue	49	—	unknown	19:35–21:35 (good, 2.0 h)	79.2° 16:00	10.1	41%	135.1°
2036-02-20 Wed	48	—	unknown	19:35–21:30 (good, 1.92 h)	79.1° 15:55	10.06	32%	125.0°
2036-02-21 Thu	46	—	unknown	19:35–21:25 (good, 1.83 h)	79.1° 15:55	10.02	23%	114.5°
2036-02-22 Fri	44	—	unknown	19:35–21:20 (good, 1.75 h)	79.1° 15:50	9.97	16%	103.9°
2036-02-23 Sat	41	—	unknown	19:40–21:15 (good, 1.58 h)	79.2° 15:45	9.93	10%	93.2°
2036-02-24 Sun	39	—	unknown	19:40–21:15 (good, 1.58 h)	79.2° 15:40	9.89	5%	82.3°
2036-02-25 Mon	38	—	unknown	19:40–21:10 (good, 1.5 h)	79.1° 15:35	9.84	2%	71.5°
2036-02-26 Tue	36	—	unknown	19:40–21:05 (good, 1.42 h)	79.1° 15:35	9.8	0%	60.6°
2036-02-27 Wed	33	—	unknown	19:45–21:00 (good, 1.25 h)	79.1° 15:30	9.76	0%	50.0°
2036-02-28 Thu	32	—	unknown	19:45–20:55 (good, 1.17 h)	79.2° 15:25	9.71	3%	39.9°
2036-02-29 Fri	28	—	unknown	19:45–20:55 (good, 1.17 h)	79.1° 15:20	9.67	7%	31.0°
2036-03-01 Sat	25	—	unknown	19:45–20:45 (good, 1.0 h)	79.1° 15:15	9.62	14%	25.2°
2036-03-02 Sun	20	—	unknown	19:50–20:35 (good, 0.75 h)	79.1° 15:15	9.57	22%	24.9°
2036-03-03 Mon	16	—	unknown	19:50–20:20 (good, 0.5 h)	79.2° 15:10	9.53	31%	30.5°
2036-03-04 Tue	12	—	unknown	19:50–19:55 (good, 0.08 h)	79.2° 15:05	9.48	42%	39.9°
2036-03-05 Wed	10	—	unknown	19:50–21:00 (marginal, 1.17 h)	79.1° 15:00	9.44	53%	51.1°
2036-03-06 Thu	8	—	unknown	19:55–20:50 (marginal, 0.92 h)	79.1° 15:00	9.39	64%	63.4°
2036-03-07 Fri	8	—	unknown	19:55–20:45 (marginal, 0.83 h)	79.1° 14:55	9.34	75%	76.3°
2036-03-08 Sat	8	—	unknown	19:55–20:45 (marginal, 0.83 h)	79.2° 14:50	9.29	84%	89.5°
2036-03-09 Sun	9	—	unknown	19:25–20:45 (marginal, 1.33 h)	79.2° 14:45	9.24	92%	102.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-02-09&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.