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: 02-24 (24), 02-25 (23), 02-26 (23), 03-03 (23), 03-04 (23) — by astronomy; check the weather when the night is within four days.

2048-02-05astronomy score per night — click a bar for that night2048-03-05

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2048-02-05 Wed	8	—	unknown	05:25–05:55 (marginal, 0.5 h)	87.2° 12:20	10.63	63%	113.6°
2048-02-06 Thu	8	—	unknown	05:25–05:55 (marginal, 0.5 h)	87.2° 12:15	10.6	52%	106.2°
2048-02-07 Fri	8	—	unknown	05:20–05:55 (marginal, 0.58 h)	87.2° 12:15	10.56	41%	98.0°
2048-02-08 Sat	9	—	unknown	05:15–05:55 (marginal, 0.67 h)	87.2° 12:10	10.53	30%	89.5°
2048-02-09 Sun	10	—	unknown	05:10–06:25 (marginal, 1.25 h)	87.2° 12:05	10.49	20%	80.9°
2048-02-10 Mon	11	—	unknown	05:45–05:50 (good, 0.08 h)	87.2° 12:00	10.45	12%	72.7°
2048-02-11 Tue	11	—	unknown	05:40–05:50 (good, 0.17 h)	87.2° 11:55	10.41	5%	65.3°
2048-02-12 Wed	13	—	unknown	05:35–05:50 (good, 0.25 h)	87.2° 11:50	10.38	2%	59.3°
2048-02-13 Thu	14	—	unknown	05:30–05:50 (good, 0.33 h)	87.2° 11:45	10.34	0%	55.0°
2048-02-14 Fri	14	—	unknown	05:25–05:45 (good, 0.33 h)	87.2° 11:40	10.3	1%	52.9°
2048-02-15 Sat	15	—	unknown	05:20–05:45 (good, 0.42 h)	87.2° 11:35	10.26	4%	53.2°
2048-02-16 Sun	16	—	unknown	05:20–05:45 (good, 0.42 h)	87.2° 11:35	10.22	10%	55.7°
2048-02-17 Mon	17	—	unknown	05:15–05:45 (good, 0.5 h)	87.2° 11:30	10.18	16%	59.8°
2048-02-18 Tue	18	—	unknown	05:10–05:40 (good, 0.5 h)	87.2° 11:25	10.14	24%	65.2°
2048-02-19 Wed	19	—	unknown	05:05–05:40 (good, 0.58 h)	87.2° 11:20	10.1	33%	71.4°
2048-02-20 Thu	20	—	unknown	05:05–05:40 (good, 0.58 h)	87.2° 11:20	10.05	42%	78.1°
2048-02-21 Fri	20	—	unknown	05:00–05:35 (good, 0.58 h)	87.2° 11:15	10.01	51%	85.1°
2048-02-22 Sat	22	—	unknown	04:55–05:35 (good, 0.67 h)	87.2° 11:10	9.97	61%	92.3°
2048-02-23 Sun	22	—	unknown	04:50–05:35 (good, 0.75 h)	87.2° 11:05	9.93	70%	99.4°
2048-02-24 Mon	24	—	unknown	04:45–05:35 (good, 0.83 h)	87.2° 11:00	9.88	78%	106.4°
2048-02-25 Tue	23	—	unknown	04:55–05:30 (good, 0.58 h)	87.2° 11:00	9.84	86%	113.0°
2048-02-26 Wed	23	—	unknown	04:50–05:30 (good, 0.67 h)	87.2° 10:55	9.8	92%	118.9°
2048-02-27 Thu	22	—	unknown	04:45–05:30 (good, 0.75 h)	87.2° 10:50	9.75	97%	123.5°
2048-02-28 Fri	21	—	unknown	04:45–05:25 (good, 0.67 h)	87.2° 10:45	9.71	99%	126.5°
2048-02-29 Sat	22	—	unknown	04:40–05:25 (good, 0.75 h)	87.2° 10:40	9.66	100%	127.1°
2048-03-01 Sun	22	—	unknown	04:35–05:25 (good, 0.83 h)	87.2° 10:40	9.62	98%	125.3°
2048-03-02 Mon	22	—	unknown	04:30–05:20 (good, 0.83 h)	87.2° 10:35	9.57	93%	121.2°
2048-03-03 Tue	23	—	unknown	04:30–05:20 (good, 0.83 h)	87.2° 10:30	9.52	86%	115.2°
2048-03-04 Wed	23	—	unknown	04:30–05:20 (good, 0.83 h)	87.2° 10:25	9.48	77%	107.9°
2048-03-05 Thu	22	—	unknown	04:25–05:15 (good, 0.83 h)	87.2° 10:25	9.43	67%	99.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2048-02-05&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.