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: 02-19 (49), 02-20 (48), 02-21 (46), 02-22 (43), 02-23 (41) — by astronomy; check the weather when the night is within four days.

2044-02-19astronomy score per night — click a bar for that night2044-03-19

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2044-02-19 Fri	49	—	unknown	19:35–21:35 (good, 2.0 h)	79.2° 16:00	10.1	59%	157.2°
2044-02-20 Sat	48	—	unknown	19:35–21:30 (good, 1.92 h)	79.2° 15:55	10.06	49%	147.7°
2044-02-21 Sun	46	—	unknown	19:35–21:25 (good, 1.83 h)	79.2° 15:55	10.01	40%	137.1°
2044-02-22 Mon	43	—	unknown	19:40–21:20 (good, 1.67 h)	79.2° 15:50	9.97	31%	126.1°
2044-02-23 Tue	41	—	unknown	19:40–21:15 (good, 1.58 h)	79.2° 15:45	9.93	22%	114.8°
2044-02-24 Wed	39	—	unknown	19:40–21:15 (good, 1.58 h)	79.2° 15:40	9.89	15%	103.3°
2044-02-25 Thu	38	—	unknown	19:40–21:10 (good, 1.5 h)	79.2° 15:35	9.84	9%	91.5°
2044-02-26 Fri	36	—	unknown	19:40–21:05 (good, 1.42 h)	79.2° 15:35	9.8	4%	79.5°
2044-02-27 Sat	33	—	unknown	19:45–21:00 (good, 1.25 h)	79.2° 15:30	9.75	1%	67.3°
2044-02-28 Sun	32	—	unknown	19:45–21:00 (good, 1.25 h)	79.2° 15:25	9.71	0%	54.9°
2044-02-29 Mon	30	—	unknown	19:45–20:55 (good, 1.17 h)	79.2° 15:20	9.66	1%	42.5°
2044-03-01 Tue	28	—	unknown	19:45–20:50 (good, 1.08 h)	79.2° 15:15	9.62	5%	30.5°
2044-03-02 Wed	24	—	unknown	19:50–20:40 (good, 0.83 h)	79.2° 15:15	9.57	11%	20.2°
2044-03-03 Thu	20	—	unknown	19:50–20:30 (good, 0.67 h)	79.2° 15:10	9.53	19%	15.8°
2044-03-04 Fri	15	—	unknown	19:50–20:20 (good, 0.5 h)	79.2° 15:05	9.48	28%	21.6°
2044-03-05 Sat	12	—	unknown	19:50–21:05 (marginal, 1.25 h)	79.2° 15:00	9.43	39%	32.8°
2044-03-06 Sun	9	—	unknown	19:55–20:55 (marginal, 1.0 h)	79.2° 15:00	9.38	51%	45.5°
2044-03-07 Mon	7	—	unknown	19:55–20:45 (marginal, 0.83 h)	79.2° 14:55	9.34	62%	58.8°
2044-03-08 Tue	7	—	unknown	19:55–20:40 (marginal, 0.75 h)	79.2° 14:50	9.29	73%	72.3°
2044-03-09 Wed	7	—	unknown	19:55–20:40 (marginal, 0.75 h)	79.2° 14:45	9.24	82%	85.9°
2044-03-10 Thu	7	—	unknown	19:55–20:45 (marginal, 0.83 h)	79.2° 14:40	9.19	90%	99.4°
2044-03-11 Fri	7	—	unknown	20:00–20:40 (marginal, 0.67 h)	79.2° 14:40	9.14	96%	112.8°
2044-03-12 Sat	7	—	unknown	20:00–20:35 (marginal, 0.58 h)	79.2° 14:35	9.09	99%	125.9°
2044-03-13 Sun	6	—	unknown	20:00–20:30 (marginal, 0.5 h)	79.2° 14:30	9.04	100%	138.4°
2044-03-14 Mon	6	—	unknown	20:00–20:30 (marginal, 0.5 h)	79.2° 14:25	8.99	99%	150.1°
2044-03-15 Tue	5	—	unknown	20:05–20:25 (marginal, 0.33 h)	79.2° 14:20	8.94	95%	159.8°
2044-03-16 Wed	4	—	unknown	20:05–20:20 (marginal, 0.25 h)	79.2° 14:20	8.89	90%	164.3°
2044-03-17 Thu	3	—	unknown	20:05–20:15 (marginal, 0.17 h)	79.2° 14:15	8.84	83%	160.2°
2044-03-18 Fri	3	—	unknown	19:35–19:45 (marginal, 0.17 h)	79.2° 14:10	8.79	75%	151.3°
2044-03-19 Sat	2	—	unknown	19:35–19:40 (marginal, 0.08 h)	79.2° 14:05	8.74	66%	140.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2044-02-19&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.