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: 10-21 (100), 10-22 (100), 10-23 (100), 10-24 (100), 10-25 (100) — by astronomy; check the weather when the night is within four days.

2036-10-21astronomy score per night — click a bar for that night2036-11-19

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-10-21 Tue	100	—	unknown	22:00–06:10 (good, 8.17 h)	72.5° 03:05	10.1	7%	171.0°
2036-10-22 Wed	100	—	unknown	21:55–06:10 (good, 8.25 h)	72.5° 03:00	10.14	14%	164.0°
2036-10-23 Thu	100	—	unknown	21:50–06:15 (good, 8.42 h)	72.5° 03:00	10.18	21%	152.5°
2036-10-24 Fri	100	—	unknown	21:50–06:15 (good, 8.42 h)	72.5° 02:55	10.22	30%	140.6°
2036-10-25 Sat	100	—	unknown	21:45–05:15 (good, 8.5 h)	72.5° 02:50	10.26	39%	128.7°
2036-10-26 Sun	100	—	unknown	20:45–05:15 (good, 8.5 h)	72.5° 01:45	10.3	49%	117.0°
2036-10-27 Mon	100	—	unknown	20:45–05:20 (good, 8.58 h)	72.5° 01:40	10.34	58%	105.3°
2036-10-28 Tue	100	—	unknown	20:50–05:20 (good, 8.5 h)	72.5° 01:40	10.37	67%	93.6°
2036-10-29 Wed	100	—	unknown	21:05–05:20 (good, 8.25 h)	72.5° 01:35	10.41	76%	81.8°
2036-10-30 Thu	100	—	unknown	22:25–05:20 (good, 6.92 h)	72.5° 01:30	10.45	83%	69.9°
2036-10-31 Fri	97	—	unknown	01:00–05:20 (good, 4.33 h)	72.5° 01:25	10.49	90%	57.9°
2036-11-01 Sat	89	—	unknown	04:40–05:25 (good, 0.75 h)	72.5° 01:20	10.52	95%	45.7°
2036-11-02 Sun	44	—	unknown	22:50–05:25 (marginal, 6.58 h)	72.5° 01:20	10.56	98%	33.3°
2036-11-03 Mon	32	—	unknown	02:10–05:25 (marginal, 3.25 h)	72.5° 01:15	10.59	100%	21.1°
2036-11-04 Tue	26	—	unknown	03:15–05:25 (marginal, 2.17 h)	72.5° 01:10	10.63	99%	10.7°
2036-11-05 Wed	31	—	unknown	19:55–00:00 (marginal, 4.08 h)	72.5° 01:05	10.66	96%	11.7°
2036-11-06 Thu	42	—	unknown	19:40–03:35 (marginal, 7.92 h)	72.5° 01:05	10.7	90%	23.0°
2036-11-07 Fri	74	—	unknown	19:55–20:15 (good, 0.33 h)	72.5° 01:00	10.73	83%	36.2°
2036-11-08 Sat	87	—	unknown	19:50–01:05 (good, 5.25 h)	72.5° 00:55	10.76	73%	49.8°
2036-11-09 Sun	95	—	unknown	19:45–04:15 (good, 8.5 h)	72.5° 00:50	10.79	63%	63.6°
2036-11-10 Mon	100	—	unknown	19:40–05:35 (good, 9.92 h)	72.5° 00:45	10.83	52%	77.5°
2036-11-11 Tue	100	—	unknown	19:35–05:35 (good, 10.0 h)	72.5° 00:45	10.86	40%	91.5°
2036-11-12 Wed	100	—	unknown	19:35–05:35 (good, 10.0 h)	72.5° 00:40	10.89	29%	105.4°
2036-11-13 Thu	100	—	unknown	19:30–05:35 (good, 10.08 h)	72.5° 00:35	10.92	20%	119.3°
2036-11-14 Fri	100	—	unknown	19:25–05:35 (good, 10.17 h)	72.5° 00:30	10.95	12%	133.1°
2036-11-15 Sat	100	—	unknown	19:20–05:40 (good, 10.33 h)	72.5° 00:25	10.98	5%	146.6°
2036-11-16 Sun	100	—	unknown	19:15–05:35 (good, 10.33 h)	72.5° 00:25	11.0	2%	159.5°
2036-11-17 Mon	100	—	unknown	19:15–05:30 (good, 10.25 h)	72.5° 00:20	11.03	0%	169.8°
2036-11-18 Tue	100	—	unknown	19:10–05:25 (good, 10.25 h)	72.5° 00:15	11.06	1%	167.9°
2036-11-19 Wed	100	—	unknown	19:05–05:20 (good, 10.25 h)	72.5° 00:10	11.08	4%	157.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-10-21&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.