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 North America Nebula: 04-21 (70), 04-22 (70), 04-23 (70), 04-24 (70), 04-19 (69) — by astronomy; check the weather when the night is within four days.

2029-04-06astronomy score per night — click a bar for that night2029-05-05

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-04-06 Fri	46	—	unknown	03:05–05:20 (good, 2.25 h)	87.2° 09:20	7.79	39%	63.6°
2029-04-07 Sat	51	—	unknown	03:00–05:15 (good, 2.25 h)	87.2° 09:15	7.73	29%	58.6°
2029-04-08 Sun	55	—	unknown	02:55–05:15 (good, 2.33 h)	87.2° 09:10	7.68	21%	55.1°
2029-04-09 Mon	59	—	unknown	02:50–05:15 (good, 2.42 h)	87.2° 09:05	7.62	14%	53.3°
2029-04-10 Tue	60	—	unknown	02:45–05:10 (good, 2.42 h)	87.2° 09:00	7.56	8%	53.3°
2029-04-11 Wed	61	—	unknown	02:45–05:10 (good, 2.42 h)	87.2° 09:00	7.51	4%	55.2°
2029-04-12 Thu	62	—	unknown	02:40–05:05 (good, 2.42 h)	87.2° 08:55	7.45	1%	58.6°
2029-04-13 Fri	63	—	unknown	02:35–05:05 (good, 2.5 h)	87.2° 08:50	7.39	0%	63.4°
2029-04-14 Sat	65	—	unknown	02:30–05:05 (good, 2.58 h)	87.2° 08:45	7.33	1%	69.1°
2029-04-15 Sun	65	—	unknown	02:25–05:00 (good, 2.58 h)	87.2° 08:40	7.28	4%	75.6°
2029-04-16 Mon	66	—	unknown	02:25–05:00 (good, 2.58 h)	87.2° 08:40	7.22	8%	82.6°
2029-04-17 Tue	68	—	unknown	02:20–05:00 (good, 2.67 h)	87.2° 08:35	7.16	14%	89.9°
2029-04-18 Wed	68	—	unknown	02:15–04:55 (good, 2.67 h)	87.2° 08:30	7.1	22%	97.3°
2029-04-19 Thu	69	—	unknown	02:10–04:55 (good, 2.75 h)	87.2° 08:25	7.05	31%	104.6°
2029-04-20 Fri	69	—	unknown	02:10–04:50 (good, 2.67 h)	87.2° 08:25	6.99	40%	111.6°
2029-04-21 Sat	70	—	unknown	02:10–04:50 (good, 2.67 h)	87.2° 08:20	6.93	51%	117.8°
2029-04-22 Sun	70	—	unknown	02:05–04:50 (good, 2.75 h)	87.2° 08:15	6.87	62%	122.9°
2029-04-23 Mon	70	—	unknown	02:05–04:45 (good, 2.67 h)	87.2° 08:10	6.81	73%	126.2°
2029-04-24 Tue	70	—	unknown	02:00–04:45 (good, 2.75 h)	87.2° 08:05	6.75	82%	127.0°
2029-04-25 Wed	63	—	unknown	02:00–04:40 (good, 2.67 h)	87.2° 08:05	6.7	90%	125.0°
2029-04-26 Thu	63	—	unknown	01:55–04:40 (good, 2.75 h)	87.2° 08:00	6.64	96%	120.5°
2029-04-27 Fri	59	—	unknown	02:00–04:40 (good, 2.67 h)	87.2° 07:55	6.58	99%	113.8°
2029-04-28 Sat	53	—	unknown	02:00–04:35 (good, 2.58 h)	87.2° 07:50	6.52	100%	105.8°
2029-04-29 Sun	49	—	unknown	02:00–04:35 (good, 2.58 h)	87.2° 07:45	6.46	97%	97.1°
2029-04-30 Mon	47	—	unknown	02:00–04:35 (good, 2.58 h)	87.2° 07:45	6.41	91%	88.4°
2029-05-01 Tue	45	—	unknown	01:55–04:30 (good, 2.58 h)	87.2° 07:40	6.35	84%	79.9°
2029-05-02 Wed	47	—	unknown	01:45–04:30 (good, 2.75 h)	87.2° 07:35	6.29	75%	72.1°
2029-05-03 Thu	53	—	unknown	01:15–04:25 (good, 3.17 h)	87.2° 07:30	6.23	65%	65.3°
2029-05-04 Fri	62	—	unknown	01:15–04:25 (good, 3.17 h)	87.2° 07:30	6.17	55%	59.7°
2029-05-05 Sat	69	—	unknown	01:10–04:25 (good, 3.25 h)	87.2° 07:25	6.12	45%	55.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-04-06&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.