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: 10-20 (100), 10-21 (100), 10-22 (100), 10-23 (100), 10-24 (100) — by astronomy; check the weather when the night is within four days.

2030-10-16astronomy score per night — click a bar for that night2030-11-14

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2030-10-16 Wed	52	—	unknown	22:00–06:05 (marginal, 8.08 h)	72.5° 03:25	9.87	75%	25.0°
2030-10-17 Thu	79	—	unknown	22:15–02:20 (good, 4.08 h)	72.5° 03:25	9.91	66%	36.8°
2030-10-18 Fri	87	—	unknown	22:15–06:05 (good, 7.83 h)	72.5° 03:20	9.95	57%	48.6°
2030-10-19 Sat	95	—	unknown	22:10–06:10 (good, 8.0 h)	72.5° 03:15	9.99	47%	60.7°
2030-10-20 Sun	100	—	unknown	22:05–06:10 (good, 8.08 h)	72.5° 03:10	10.03	37%	73.0°
2030-10-21 Mon	100	—	unknown	22:00–06:10 (good, 8.17 h)	72.5° 03:05	10.08	28%	85.6°
2030-10-22 Tue	100	—	unknown	22:00–06:10 (good, 8.17 h)	72.5° 03:05	10.12	19%	98.6°
2030-10-23 Wed	100	—	unknown	21:55–06:15 (good, 8.33 h)	72.5° 03:00	10.16	11%	112.1°
2030-10-24 Thu	100	—	unknown	21:50–06:15 (good, 8.42 h)	72.5° 02:55	10.2	5%	126.0°
2030-10-25 Fri	100	—	unknown	21:45–06:15 (good, 8.5 h)	72.5° 02:50	10.24	1%	140.2°
2030-10-26 Sat	100	—	unknown	21:40–05:15 (good, 8.58 h)	72.5° 02:50	10.28	0%	154.8°
2030-10-27 Sun	100	—	unknown	20:40–05:15 (good, 8.58 h)	72.5° 01:45	10.32	2%	169.3°
2030-10-28 Mon	100	—	unknown	20:35–05:20 (good, 8.75 h)	72.5° 01:40	10.35	6%	174.1°
2030-10-29 Tue	100	—	unknown	20:30–05:20 (good, 8.83 h)	72.5° 01:35	10.39	13%	160.0°
2030-10-30 Wed	100	—	unknown	20:25–05:20 (good, 8.92 h)	72.5° 01:30	10.43	22%	145.5°
2030-10-31 Thu	100	—	unknown	20:25–05:20 (good, 8.92 h)	72.5° 01:30	10.47	32%	131.1°
2030-11-01 Fri	100	—	unknown	20:25–05:20 (good, 8.92 h)	72.5° 01:25	10.5	44%	117.1°
2030-11-02 Sat	100	—	unknown	20:25–05:25 (good, 9.0 h)	72.5° 01:20	10.54	55%	103.4°
2030-11-03 Sun	100	—	unknown	20:30–05:25 (good, 8.92 h)	72.5° 01:15	10.57	65%	90.0°
2030-11-04 Mon	100	—	unknown	21:15–05:25 (good, 8.17 h)	72.5° 01:10	10.61	75%	76.9°
2030-11-05 Tue	100	—	unknown	22:55–05:25 (good, 6.5 h)	72.5° 01:10	10.64	83%	64.1°
2030-11-06 Wed	91	—	unknown	02:10–05:30 (good, 3.33 h)	72.5° 01:05	10.68	90%	51.5°
2030-11-07 Thu	83	—	unknown	05:15–05:30 (good, 0.25 h)	72.5° 01:00	10.71	95%	39.0°
2030-11-08 Fri	37	—	unknown	01:25–05:30 (marginal, 4.08 h)	72.5° 00:55	10.74	98%	26.8°
2030-11-09 Sat	28	—	unknown	02:35–05:30 (marginal, 2.92 h)	72.5° 00:55	10.78	100%	14.8°
2030-11-10 Sun	24	—	unknown	04:05–05:30 (marginal, 1.42 h)	72.5° 00:50	10.81	99%	4.2°
2030-11-11 Mon	29	—	unknown	19:40–23:00 (marginal, 3.33 h)	72.5° 00:45	10.84	97%	10.1°
2030-11-12 Tue	38	—	unknown	19:25–00:40 (marginal, 5.25 h)	72.5° 00:40	10.87	93%	21.6°
2030-11-13 Wed	61	—	unknown	19:30–19:35 (good, 0.08 h)	72.5° 00:35	10.9	88%	33.3°
2030-11-14 Thu	84	—	unknown	19:25–23:00 (good, 3.58 h)	72.5° 00:35	10.93	81%	45.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2030-10-16&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.