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: 11-02 (100), 11-03 (100), 11-04 (100), 11-05 (100), 11-06 (100) — by astronomy; check the weather when the night is within four days.

2027-11-02astronomy score per night — click a bar for that night2027-12-01

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2027-11-02 Tue	100	—	unknown	20:15–05:25 (good, 9.17 h)	72.5° 01:20	10.53	20%	147.0°
2027-11-03 Wed	100	—	unknown	20:15–05:25 (good, 9.17 h)	72.5° 01:15	10.57	28%	134.8°
2027-11-04 Thu	100	—	unknown	20:10–05:25 (good, 9.25 h)	72.5° 01:15	10.6	37%	122.8°
2027-11-05 Fri	100	—	unknown	20:10–05:25 (good, 9.25 h)	72.5° 01:10	10.64	46%	110.9°
2027-11-06 Sat	100	—	unknown	20:10–05:25 (good, 9.25 h)	72.5° 01:05	10.67	56%	99.1°
2027-11-07 Sun	100	—	unknown	20:15–05:30 (good, 9.25 h)	72.5° 01:00	10.7	65%	87.2°
2027-11-08 Mon	100	—	unknown	21:00–05:30 (good, 8.5 h)	72.5° 01:00	10.74	74%	75.2°
2027-11-09 Tue	99	—	unknown	22:40–05:30 (good, 6.83 h)	72.5° 00:55	10.77	82%	63.0°
2027-11-10 Wed	91	—	unknown	02:00–05:30 (good, 3.5 h)	72.5° 00:50	10.8	89%	50.5°
2027-11-11 Thu	82	—	unknown	05:10–05:35 (good, 0.42 h)	72.5° 00:45	10.83	94%	37.8°
2027-11-12 Fri	36	—	unknown	01:20–05:35 (marginal, 4.25 h)	72.5° 00:40	10.86	98%	24.7°
2027-11-13 Sat	26	—	unknown	02:55–05:35 (marginal, 2.67 h)	72.5° 00:40	10.89	100%	11.3°
2027-11-14 Sun	23	—	unknown	19:45–21:00 (marginal, 1.25 h)	72.5° 00:35	10.92	99%	2.5°
2027-11-15 Mon	31	—	unknown	19:20–23:10 (marginal, 3.83 h)	72.5° 00:30	10.95	96%	16.4°
2027-11-16 Tue	44	—	unknown	19:05–01:55 (marginal, 6.83 h)	72.5° 00:25	10.98	90%	30.5°
2027-11-17 Wed	82	—	unknown	19:15–20:00 (good, 0.75 h)	72.5° 00:20	11.01	83%	44.7°
2027-11-18 Thu	92	—	unknown	19:10–02:25 (good, 7.25 h)	72.5° 00:20	11.04	73%	58.9°
2027-11-19 Fri	100	—	unknown	19:10–04:25 (good, 9.25 h)	72.5° 00:15	11.06	63%	73.1°
2027-11-20 Sat	100	—	unknown	19:05–05:05 (good, 10.0 h)	72.5° 00:10	11.09	51%	87.3°
2027-11-21 Sun	100	—	unknown	19:00–05:10 (good, 10.17 h)	72.5° 00:05	11.11	40%	101.4°
2027-11-22 Mon	100	—	unknown	18:55–05:10 (good, 10.25 h)	72.5° 00:00	11.14	29%	115.3°
2027-11-23 Tue	100	—	unknown	18:55–05:10 (good, 10.25 h)	72.5° 00:00	11.16	20%	129.2°
2027-11-24 Wed	100	—	unknown	18:50–05:05 (good, 10.25 h)	72.5° 23:55	11.19	12%	142.9°
2027-11-25 Thu	100	—	unknown	18:45–05:00 (good, 10.25 h)	72.5° 23:50	11.21	6%	156.5°
2027-11-26 Fri	100	—	unknown	18:40–05:00 (good, 10.33 h)	72.5° 23:45	11.23	2%	169.8°
2027-11-27 Sat	100	—	unknown	18:35–04:55 (good, 10.33 h)	72.5° 23:45	11.25	0%	177.0°
2027-11-28 Sun	100	—	unknown	18:35–04:50 (good, 10.25 h)	72.5° 23:40	11.27	1%	164.1°
2027-11-29 Mon	100	—	unknown	18:35–04:45 (good, 10.17 h)	72.5° 23:35	11.29	3%	151.4°
2027-11-30 Tue	100	—	unknown	18:35–04:40 (good, 10.08 h)	72.5° 23:30	11.31	8%	139.0°
2027-12-01 Wed	100	—	unknown	18:35–04:40 (good, 10.08 h)	72.5° 23:25	11.33	14%	126.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2027-11-02&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.