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 Seven Sisters: 03-14 (44), 03-15 (43), 03-16 (41), 03-12 (40), 03-13 (40) — by astronomy; check the weather when the night is within four days.

2036-03-05astronomy score per night — click a bar for that night2036-04-03

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-03-05 Wed	25	—	unknown	19:50–22:45 (marginal, 2.92 h)	72.5° 17:15	9.44	53%	21.2°
2036-03-06 Thu	18	—	unknown	19:55–22:30 (marginal, 2.58 h)	72.5° 17:10	9.39	64%	34.4°
2036-03-07 Fri	17	—	unknown	19:55–22:25 (marginal, 2.5 h)	72.5° 17:05	9.34	75%	48.2°
2036-03-08 Sat	18	—	unknown	19:55–22:20 (marginal, 2.42 h)	72.5° 17:00	9.29	84%	62.5°
2036-03-09 Sun	21	—	unknown	19:55–22:20 (marginal, 2.42 h)	72.5° 17:00	9.24	92%	77.0°
2036-03-10 Mon	27	—	unknown	19:55–20:50 (good, 0.92 h)	72.5° 16:55	9.2	97%	91.6°
2036-03-11 Tue	33	—	unknown	20:00–21:40 (good, 1.67 h)	72.5° 16:50	9.15	100%	106.0°
2036-03-12 Wed	40	—	unknown	20:00–21:45 (good, 1.75 h)	72.5° 16:45	9.1	100%	120.2°
2036-03-13 Thu	40	—	unknown	20:00–21:45 (good, 1.75 h)	72.5° 16:40	9.05	97%	134.1°
2036-03-14 Fri	44	—	unknown	20:00–21:40 (good, 1.67 h)	72.5° 16:40	9.0	92%	147.4°
2036-03-15 Sat	43	—	unknown	20:05–21:45 (good, 1.67 h)	72.5° 16:35	8.95	85%	159.7°
2036-03-16 Sun	41	—	unknown	20:05–21:40 (good, 1.58 h)	72.5° 16:30	8.9	77%	169.4°
2036-03-17 Mon	39	—	unknown	20:05–21:35 (good, 1.5 h)	72.5° 16:25	8.85	68%	168.1°
2036-03-18 Tue	37	—	unknown	20:05–21:35 (good, 1.5 h)	72.5° 16:25	8.8	58%	158.3°
2036-03-19 Wed	34	—	unknown	20:10–21:30 (good, 1.33 h)	72.5° 16:20	8.74	48%	147.1°
2036-03-20 Thu	33	—	unknown	20:10–21:25 (good, 1.25 h)	72.5° 16:15	8.69	39%	135.6°
2036-03-21 Fri	31	—	unknown	20:10–21:20 (good, 1.17 h)	72.5° 16:10	8.64	30%	124.0°
2036-03-22 Sat	30	—	unknown	20:10–21:20 (good, 1.17 h)	72.5° 16:05	8.59	22%	112.4°
2036-03-23 Sun	27	—	unknown	20:15–21:15 (good, 1.0 h)	72.5° 16:05	8.54	14%	100.6°
2036-03-24 Mon	25	—	unknown	20:15–21:10 (good, 0.92 h)	72.5° 16:00	8.48	8%	88.7°
2036-03-25 Tue	25	—	unknown	20:15–21:05 (good, 0.83 h)	72.5° 15:55	8.43	4%	76.6°
2036-03-26 Wed	23	—	unknown	20:15–21:00 (good, 0.75 h)	72.5° 15:50	8.38	1%	64.3°
2036-03-27 Thu	20	—	unknown	20:20–21:00 (good, 0.67 h)	72.5° 15:45	8.32	0%	51.7°
2036-03-28 Fri	19	—	unknown	20:20–20:55 (good, 0.58 h)	72.5° 15:45	8.27	1%	39.1°
2036-03-29 Sat	18	—	unknown	20:20–20:50 (good, 0.5 h)	72.5° 15:40	8.21	5%	26.5°
2036-03-30 Sun	13	—	unknown	21:25–21:40 (good, 0.25 h)	72.5° 16:35	8.16	10%	14.7°
2036-03-31 Mon	11	—	unknown	21:25–21:35 (good, 0.17 h)	72.5° 16:30	8.11	18%	9.5°
2036-04-01 Tue	8	—	unknown	21:25–22:05 (marginal, 0.67 h)	72.5° 16:30	8.05	27%	18.4°
2036-04-02 Wed	5	—	unknown	21:25–22:00 (marginal, 0.58 h)	72.5° 16:25	8.0	38%	31.1°
2036-04-03 Thu	4	—	unknown	21:30–21:55 (marginal, 0.42 h)	72.5° 16:20	7.94	49%	44.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-03-05&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.