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: 01-02 (100), 01-03 (100), 01-04 (100), 01-05 (100), 01-06 (100) — by astronomy; check the weather when the night is within four days.

2029-01-01astronomy score per night — click a bar for that night2029-01-30

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-01-01 Mon	78	—	unknown	18:45–22:40 (good, 3.92 h)	79.1° 19:10	11.45	98%	85.1°
2029-01-02 Tue	100	—	unknown	18:45–00:05 (good, 5.33 h)	79.1° 19:05	11.44	94%	98.7°
2029-01-03 Wed	100	—	unknown	18:45–00:20 (good, 5.58 h)	79.1° 19:00	11.42	87%	112.5°
2029-01-04 Thu	100	—	unknown	18:45–00:20 (good, 5.58 h)	79.1° 19:00	11.41	78%	126.1°
2029-01-05 Fri	100	—	unknown	18:45–00:20 (good, 5.58 h)	79.1° 18:55	11.4	68%	139.5°
2029-01-06 Sat	100	—	unknown	18:50–00:20 (good, 5.5 h)	79.1° 18:50	11.38	57%	152.2°
2029-01-07 Sun	100	—	unknown	18:50–00:20 (good, 5.5 h)	79.1° 18:45	11.37	46%	162.6°
2029-01-08 Mon	100	—	unknown	18:50–00:15 (good, 5.42 h)	79.1° 18:40	11.35	35%	165.1°
2029-01-09 Tue	100	—	unknown	18:50–00:10 (good, 5.33 h)	79.1° 18:40	11.34	24%	157.1°
2029-01-10 Wed	100	—	unknown	18:50–00:05 (good, 5.25 h)	79.1° 18:35	11.32	16%	145.5°
2029-01-11 Thu	100	—	unknown	18:55–00:05 (good, 5.17 h)	79.1° 18:30	11.3	8%	132.9°
2029-01-12 Fri	100	—	unknown	18:55–00:00 (good, 5.08 h)	79.1° 18:25	11.28	4%	120.2°
2029-01-13 Sat	100	—	unknown	18:55–23:55 (good, 5.0 h)	79.1° 18:25	11.26	1%	107.5°
2029-01-14 Sun	100	—	unknown	18:55–23:50 (good, 4.92 h)	79.1° 18:20	11.24	0%	95.0°
2029-01-15 Mon	100	—	unknown	18:55–23:45 (good, 4.83 h)	79.1° 18:15	11.22	2%	82.6°
2029-01-16 Tue	100	—	unknown	18:55–23:45 (good, 4.83 h)	79.1° 18:10	11.2	5%	70.6°
2029-01-17 Wed	100	—	unknown	19:00–23:40 (good, 4.67 h)	79.1° 18:05	11.17	10%	58.8°
2029-01-18 Thu	93	—	unknown	19:00–23:35 (good, 4.58 h)	79.1° 18:05	11.15	17%	47.4°
2029-01-19 Fri	88	—	unknown	19:00–23:30 (good, 4.5 h)	79.1° 18:00	11.13	24%	36.3°
2029-01-20 Sat	76	—	unknown	19:00–23:30 (good, 4.5 h)	79.1° 17:55	11.1	33%	26.0°
2029-01-21 Sun	60	—	unknown	19:05–23:00 (good, 3.92 h)	79.1° 17:50	11.08	42%	17.5°
2029-01-22 Mon	46	—	unknown	19:05–21:20 (good, 2.25 h)	79.1° 17:45	11.05	51%	14.5°
2029-01-23 Tue	33	—	unknown	19:05–23:35 (marginal, 4.5 h)	79.1° 17:45	11.02	61%	19.9°
2029-01-24 Wed	23	—	unknown	19:05–23:15 (marginal, 4.17 h)	79.1° 17:40	10.99	70%	29.7°
2029-01-25 Thu	22	—	unknown	19:05–23:05 (marginal, 4.0 h)	79.1° 17:35	10.96	79%	41.1°
2029-01-26 Fri	24	—	unknown	19:10–23:00 (marginal, 3.83 h)	79.1° 17:30	10.94	87%	53.3°
2029-01-27 Sat	30	—	unknown	19:10–23:00 (marginal, 3.83 h)	79.1° 17:30	10.91	93%	66.2°
2029-01-28 Sun	40	—	unknown	19:10–20:15 (good, 1.08 h)	79.1° 17:25	10.88	98%	79.6°
2029-01-29 Mon	52	—	unknown	19:10–21:35 (good, 2.42 h)	79.1° 17:20	10.84	100%	93.4°
2029-01-30 Tue	66	—	unknown	19:10–22:25 (good, 3.25 h)	79.1° 17:15	10.81	99%	107.4°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-01-01&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.