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: 01-21 (100), 01-22 (100), 01-23 (100), 01-24 (100), 01-25 (100) — by astronomy; check the weather when the night is within four days.

2036-01-21astronomy score per night — click a bar for that night2036-02-19

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-01-21 Mon	100	—	unknown	19:00–23:25 (good, 4.42 h)	79.2° 17:55	11.09	34%	150.1°
2036-01-22 Tue	100	—	unknown	19:05–23:25 (good, 4.33 h)	79.2° 17:50	11.07	25%	141.9°
2036-01-23 Wed	100	—	unknown	19:05–23:20 (good, 4.25 h)	79.1° 17:45	11.04	17%	132.4°
2036-01-24 Thu	100	—	unknown	19:05–23:15 (good, 4.17 h)	79.1° 17:45	11.01	11%	122.2°
2036-01-25 Fri	100	—	unknown	19:05–23:10 (good, 4.08 h)	79.1° 17:40	10.98	6%	111.7°
2036-01-26 Sat	100	—	unknown	19:05–23:05 (good, 4.0 h)	79.2° 17:35	10.96	2%	101.0°
2036-01-27 Sun	100	—	unknown	19:10–23:05 (good, 3.92 h)	79.1° 17:30	10.93	0%	90.2°
2036-01-28 Mon	100	—	unknown	19:10–23:00 (good, 3.83 h)	79.1° 17:25	10.9	0%	79.4°
2036-01-29 Tue	98	—	unknown	19:10–22:55 (good, 3.75 h)	79.1° 17:25	10.87	2%	68.5°
2036-01-30 Wed	96	—	unknown	19:10–22:50 (good, 3.67 h)	79.1° 17:20	10.84	6%	57.8°
2036-01-31 Thu	88	—	unknown	19:15–22:50 (good, 3.58 h)	79.2° 17:15	10.8	11%	47.4°
2036-02-01 Fri	78	—	unknown	19:15–22:45 (good, 3.5 h)	79.1° 17:10	10.77	18%	37.6°
2036-02-02 Sat	66	—	unknown	19:15–22:30 (good, 3.25 h)	79.1° 17:05	10.74	26%	29.3°
2036-02-03 Sun	53	—	unknown	19:15–22:15 (good, 3.0 h)	79.1° 17:05	10.7	36%	24.6°
2036-02-04 Mon	40	—	unknown	19:15–21:30 (good, 2.25 h)	79.2° 17:00	10.67	46%	25.7°
2036-02-05 Tue	29	—	unknown	19:20–22:50 (marginal, 3.5 h)	79.2° 16:55	10.64	57%	32.6°
2036-02-06 Wed	24	—	unknown	19:20–22:35 (marginal, 3.25 h)	79.1° 16:50	10.6	68%	42.8°
2036-02-07 Thu	23	—	unknown	19:20–22:30 (marginal, 3.17 h)	79.1° 16:50	10.57	78%	54.7°
2036-02-08 Fri	25	—	unknown	19:20–22:25 (marginal, 3.08 h)	79.1° 16:45	10.53	87%	67.7°
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°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-01-21&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.