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 V1057 Cyg: 01-11 (36), 01-12 (34), 01-13 (33), 01-14 (32), 01-15 (30) — by astronomy; check the weather when the night is within four days.

2029-01-11astronomy score per night — click a bar for that night2029-02-09

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-01-11 Thu	36	—	unknown	18:55–20:15 (good, 1.33 h)	87.3° 13:55	11.3	8%	87.3°
2029-01-12 Fri	34	—	unknown	18:55–20:10 (good, 1.25 h)	87.3° 13:50	11.28	4%	79.3°
2029-01-13 Sat	33	—	unknown	18:55–20:10 (good, 1.25 h)	87.3° 13:50	11.26	1%	71.9°
2029-01-14 Sun	32	—	unknown	18:55–20:05 (good, 1.17 h)	87.3° 13:45	11.24	0%	65.2°
2029-01-15 Mon	30	—	unknown	18:55–20:00 (good, 1.08 h)	87.3° 13:40	11.22	2%	59.7°
2029-01-16 Tue	28	—	unknown	18:55–19:55 (good, 1.0 h)	87.3° 13:35	11.2	5%	55.7°
2029-01-17 Wed	24	—	unknown	19:00–19:50 (good, 0.83 h)	87.3° 13:30	11.17	10%	53.4°
2029-01-18 Thu	22	—	unknown	19:00–19:40 (good, 0.67 h)	87.3° 13:30	11.15	17%	53.1°
2029-01-19 Fri	19	—	unknown	19:00–19:30 (good, 0.5 h)	87.3° 13:25	11.13	24%	54.5°
2029-01-20 Sat	16	—	unknown	19:00–19:20 (good, 0.33 h)	87.3° 13:20	11.1	33%	57.7°
2029-01-21 Sun	13	—	unknown	19:05–19:10 (good, 0.08 h)	87.3° 13:15	11.08	42%	62.2°
2029-01-22 Mon	11	—	unknown	19:05–20:05 (marginal, 1.0 h)	87.3° 13:15	11.05	51%	67.8°
2029-01-23 Tue	10	—	unknown	19:05–20:00 (marginal, 0.92 h)	87.3° 13:10	11.02	61%	74.2°
2029-01-24 Wed	9	—	unknown	19:05–19:55 (marginal, 0.83 h)	87.3° 13:05	10.99	70%	81.3°
2029-01-25 Thu	9	—	unknown	19:05–19:50 (marginal, 0.75 h)	87.3° 13:00	10.96	79%	88.9°
2029-01-26 Fri	8	—	unknown	19:10–19:50 (marginal, 0.67 h)	87.3° 12:55	10.94	87%	96.7°
2029-01-27 Sat	8	—	unknown	19:10–19:50 (marginal, 0.67 h)	87.3° 12:55	10.91	93%	104.5°
2029-01-28 Sun	8	—	unknown	19:10–19:45 (marginal, 0.58 h)	87.3° 12:50	10.88	98%	112.0°
2029-01-29 Mon	8	—	unknown	19:10–19:40 (marginal, 0.5 h)	87.3° 12:45	10.84	100%	118.6°
2029-01-30 Tue	8	—	unknown	19:10–19:35 (marginal, 0.42 h)	87.3° 12:40	10.81	99%	123.7°
2029-01-31 Wed	8	—	unknown	19:15–19:30 (marginal, 0.25 h)	87.3° 12:35	10.78	96%	126.6°
2029-02-01 Thu	8	—	unknown	05:40–06:00 (marginal, 0.33 h)	87.3° 12:35	10.75	90%	126.7°
2029-02-02 Fri	8	—	unknown	05:35–06:00 (marginal, 0.42 h)	87.3° 12:30	10.71	82%	124.0°
2029-02-03 Sat	8	—	unknown	05:30–06:00 (marginal, 0.5 h)	87.3° 12:25	10.68	72%	119.1°
2029-02-04 Sun	7	—	unknown	05:30–05:55 (marginal, 0.42 h)	87.3° 12:20	10.65	61%	112.6°
2029-02-05 Mon	8	—	unknown	05:25–05:55 (marginal, 0.5 h)	87.3° 12:20	10.61	50%	105.1°
2029-02-06 Tue	8	—	unknown	05:20–05:55 (marginal, 0.58 h)	87.3° 12:15	10.58	39%	97.2°
2029-02-07 Wed	9	—	unknown	05:15–05:55 (marginal, 0.67 h)	87.3° 12:10	10.54	28%	89.1°
2029-02-08 Thu	10	—	unknown	05:50–05:55 (good, 0.08 h)	87.3° 12:05	10.5	19%	81.2°
2029-02-09 Fri	10	—	unknown	05:45–05:50 (good, 0.08 h)	87.3° 12:00	10.47	12%	73.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-01-11&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.