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: 03-02 (13), 03-08 (12), 03-09 (12), 03-03 (11), 03-07 (11) — by astronomy; check the weather when the night is within four days.

2039-03-02astronomy score per night — click a bar for that night2039-03-31

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2039-03-02 Wed	13	—	unknown	19:45–21:15 (marginal, 1.5 h)	79.2° 15:15	9.61	48%	42.1°
2039-03-03 Thu	11	—	unknown	19:50–21:05 (marginal, 1.25 h)	79.2° 15:10	9.56	58%	52.1°
2039-03-04 Fri	10	—	unknown	19:50–21:00 (marginal, 1.17 h)	79.2° 15:10	9.52	67%	62.7°
2039-03-05 Sat	9	—	unknown	19:50–20:55 (marginal, 1.08 h)	79.2° 15:05	9.47	76%	73.8°
2039-03-06 Sun	10	—	unknown	19:50–20:55 (marginal, 1.08 h)	79.2° 15:00	9.42	84%	85.4°
2039-03-07 Mon	11	—	unknown	19:55–20:55 (marginal, 1.0 h)	79.2° 14:55	9.38	91%	97.3°
2039-03-08 Tue	12	—	unknown	19:55–20:05 (good, 0.17 h)	79.2° 14:55	9.33	96%	109.5°
2039-03-09 Wed	12	—	unknown	19:55–20:10 (good, 0.25 h)	79.2° 14:50	9.28	99%	121.8°
2039-03-10 Thu	11	—	unknown	19:55–20:05 (good, 0.17 h)	79.2° 14:45	9.23	100%	133.9°
2039-03-11 Fri	9	—	unknown	20:00–20:05 (good, 0.08 h)	79.2° 14:40	9.18	98%	145.1°
2039-03-12 Sat	10	—	unknown	20:00–20:10 (good, 0.17 h)	79.2° 14:35	9.13	93%	153.8°
2039-03-13 Sun	9	—	unknown	20:00–20:05 (good, 0.08 h)	79.2° 14:35	9.08	86%	156.5°
2039-03-14 Mon	7	—	unknown	19:30–20:30 (marginal, 1.0 h)	79.2° 14:30	9.03	77%	151.5°
2039-03-15 Tue	6	—	unknown	19:30–20:00 (marginal, 0.5 h)	79.2° 14:25	8.98	67%	141.7°
2039-03-16 Wed	5	—	unknown	19:30–19:55 (marginal, 0.42 h)	79.2° 14:20	8.93	56%	130.1°
2039-03-17 Thu	4	—	unknown	20:05–20:20 (marginal, 0.25 h)	79.2° 14:15	8.88	44%	117.9°
2039-03-18 Fri	3	—	unknown	20:05–20:15 (marginal, 0.17 h)	79.2° 14:15	8.83	33%	105.4°
2039-03-19 Sat	3	—	unknown	20:05–20:10 (marginal, 0.08 h)	79.2° 14:10	8.78	24%	92.9°
2039-03-20 Sun	1	—	unknown	19:35–19:40 (marginal, 0.08 h)	79.2° 14:05	8.73	15%	80.6°
2039-03-21 Mon	1	—	unknown	—	79.2° 14:00	8.68	8%	68.6°
2039-03-22 Tue	1	—	unknown	—	79.2° 14:00	8.63	4%	57.0°
2039-03-23 Wed	1	—	unknown	—	79.2° 13:55	8.57	1%	46.0°
2039-03-24 Thu	0	—	unknown	—	79.2° 13:50	8.52	0%	36.0°
2039-03-25 Fri	0	—	unknown	—	79.2° 13:45	8.47	2%	27.9°
2039-03-26 Sat	0	—	unknown	—	79.2° 13:40	8.42	5%	23.6°
2039-03-27 Sun	0	—	unknown	—	79.2° 14:40	8.36	10%	24.7°
2039-03-28 Mon	0	—	unknown	—	79.2° 14:35	8.31	16%	30.5°
2039-03-29 Tue	0	—	unknown	—	79.2° 14:30	8.25	23%	38.9°
2039-03-30 Wed	0	—	unknown	—	79.2° 14:25	8.2	32%	48.6°
2039-03-31 Thu	0	—	unknown	—	79.2° 14:20	8.15	41%	58.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2039-03-02&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.