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: 01-20 (100), 01-21 (100), 01-22 (100), 01-23 (100), 01-24 (100) — by astronomy; check the weather when the night is within four days.

2033-01-20astronomy score per night — click a bar for that night2033-02-18

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-01-20 Thu	100	—	unknown	19:00–23:20 (good, 4.33 h)	79.1° 17:55	11.1	75%	143.8°
2033-01-21 Fri	100	—	unknown	19:05–23:25 (good, 4.33 h)	79.1° 17:50	11.07	67%	152.7°
2033-01-22 Sat	100	—	unknown	19:05–23:20 (good, 4.25 h)	79.1° 17:50	11.05	58%	158.8°
2033-01-23 Sun	100	—	unknown	19:05–23:15 (good, 4.17 h)	79.1° 17:45	11.02	48%	159.4°
2033-01-24 Mon	100	—	unknown	19:05–23:10 (good, 4.08 h)	79.1° 17:40	10.99	38%	153.7°
2033-01-25 Tue	100	—	unknown	19:05–23:10 (good, 4.08 h)	79.1° 17:35	10.96	29%	144.3°
2033-01-26 Wed	100	—	unknown	19:10–23:05 (good, 3.92 h)	79.1° 17:30	10.93	20%	133.1°
2033-01-27 Thu	100	—	unknown	19:10–23:00 (good, 3.83 h)	79.1° 17:30	10.91	12%	120.9°
2033-01-28 Fri	99	—	unknown	19:10–22:55 (good, 3.75 h)	79.1° 17:25	10.87	6%	107.9°
2033-01-29 Sat	97	—	unknown	19:10–22:50 (good, 3.67 h)	79.1° 17:20	10.84	2%	94.3°
2033-01-30 Sun	95	—	unknown	19:10–22:50 (good, 3.67 h)	79.1° 17:15	10.81	0%	80.4°
2033-01-31 Mon	93	—	unknown	19:15–22:45 (good, 3.5 h)	79.1° 17:10	10.78	2%	66.5°
2033-02-01 Tue	88	—	unknown	19:15–22:40 (good, 3.42 h)	79.1° 17:10	10.75	6%	52.7°
2033-02-02 Wed	80	—	unknown	19:15–22:35 (good, 3.33 h)	79.1° 17:05	10.71	13%	39.6°
2033-02-03 Thu	67	—	unknown	19:15–22:35 (good, 3.33 h)	79.1° 17:00	10.68	22%	28.2°
2033-02-04 Fri	53	—	unknown	19:20–22:15 (good, 2.92 h)	79.1° 16:55	10.65	32%	20.9°
2033-02-05 Sat	40	—	unknown	19:20–21:55 (good, 2.58 h)	79.1° 16:50	10.61	43%	21.7°
2033-02-06 Sun	29	—	unknown	19:20–22:45 (marginal, 3.42 h)	79.1° 16:50	10.58	54%	29.3°
2033-02-07 Mon	24	—	unknown	19:20–22:30 (marginal, 3.17 h)	79.1° 16:45	10.54	65%	39.8°
2033-02-08 Tue	22	—	unknown	19:20–22:25 (marginal, 3.08 h)	79.1° 16:40	10.5	74%	51.2°
2033-02-09 Wed	22	—	unknown	19:25–22:20 (marginal, 2.92 h)	79.1° 16:35	10.47	82%	62.8°
2033-02-10 Thu	26	—	unknown	19:25–22:20 (marginal, 2.92 h)	79.1° 16:35	10.43	89%	74.5°
2033-02-11 Fri	30	—	unknown	19:25–20:10 (good, 0.75 h)	79.1° 16:30	10.39	95%	86.1°
2033-02-12 Sat	36	—	unknown	19:25–21:05 (good, 1.67 h)	79.1° 16:25	10.35	98%	97.5°
2033-02-13 Sun	41	—	unknown	19:30–21:30 (good, 2.0 h)	79.1° 16:20	10.31	100%	108.8°
2033-02-14 Mon	48	—	unknown	19:30–21:35 (good, 2.08 h)	79.1° 16:15	10.27	100%	119.9°
2033-02-15 Tue	48	—	unknown	19:30–21:35 (good, 2.08 h)	79.1° 16:15	10.23	98%	130.7°
2033-02-16 Wed	52	—	unknown	19:30–21:35 (good, 2.08 h)	79.1° 16:10	10.19	94%	140.9°
2033-02-17 Thu	51	—	unknown	19:35–21:30 (good, 1.92 h)	79.1° 16:05	10.15	88%	150.2°
2033-02-18 Fri	50	—	unknown	19:35–21:35 (good, 2.0 h)	79.1° 16:00	10.11	82%	157.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-01-20&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.