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 Triangulum Pinwheel: 07-11 (46), 07-10 (40), 07-09 (33), 07-08 (27), 06-25 (21) — by astronomy; check the weather when the night is within four days.

2045-06-12astronomy score per night — click a bar for that night2045-07-11

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2045-06-12 Mon	4	—	unknown	04:05–04:30 (marginal, 0.42 h)	79.2° 09:30	4.49	7%	24.0°
2045-06-13 Tue	5	—	unknown	04:00–04:30 (marginal, 0.5 h)	79.2° 09:25	4.47	2%	36.0°
2045-06-14 Wed	6	—	unknown	03:55–04:30 (marginal, 0.58 h)	79.2° 09:20	4.46	0%	49.3°
2045-06-15 Thu	7	—	unknown	03:50–04:30 (marginal, 0.67 h)	79.2° 09:20	4.45	1%	63.3°
2045-06-16 Fri	8	—	unknown	03:45–04:30 (marginal, 0.75 h)	79.2° 09:15	4.44	5%	77.6°
2045-06-17 Sat	9	—	unknown	03:15–04:30 (marginal, 1.25 h)	79.2° 09:10	4.43	11%	91.9°
2045-06-18 Sun	10	—	unknown	03:10–04:30 (marginal, 1.33 h)	79.2° 09:05	4.43	20%	106.2°
2045-06-19 Mon	11	—	unknown	03:35–03:40 (good, 0.08 h)	79.2° 09:00	4.42	30%	120.1°
2045-06-20 Tue	13	—	unknown	03:30–03:40 (good, 0.17 h)	79.2° 09:00	4.42	41%	133.6°
2045-06-21 Wed	14	—	unknown	03:25–03:40 (good, 0.25 h)	79.2° 08:55	4.42	52%	146.4°
2045-06-22 Thu	15	—	unknown	03:25–03:40 (good, 0.25 h)	79.2° 08:50	4.43	63%	157.7°
2045-06-23 Fri	17	—	unknown	03:20–03:40 (good, 0.33 h)	79.2° 08:45	4.43	73%	165.0°
2045-06-24 Sat	19	—	unknown	03:15–03:40 (good, 0.42 h)	79.2° 08:40	4.44	82%	162.7°
2045-06-25 Sun	21	—	unknown	03:10–03:40 (good, 0.5 h)	79.2° 08:40	4.45	89%	153.6°
2045-06-26 Mon	19	—	unknown	03:15–03:40 (good, 0.42 h)	79.2° 08:35	4.46	94%	142.6°
2045-06-27 Tue	20	—	unknown	03:10–03:40 (good, 0.5 h)	79.2° 08:30	4.47	98%	131.0°
2045-06-28 Wed	20	—	unknown	03:10–03:40 (good, 0.5 h)	79.2° 08:25	4.49	100%	119.3°
2045-06-29 Thu	19	—	unknown	03:10–03:45 (good, 0.58 h)	79.2° 08:25	4.51	100%	107.7°
2045-06-30 Fri	17	—	unknown	03:15–03:45 (good, 0.5 h)	79.2° 08:20	4.53	98%	96.1°
2045-07-01 Sat	15	—	unknown	02:20–03:45 (marginal, 1.42 h)	79.2° 08:15	4.55	94%	84.6°
2045-07-02 Sun	14	—	unknown	02:20–03:45 (marginal, 1.42 h)	79.2° 08:10	4.57	88%	73.1°
2045-07-03 Mon	13	—	unknown	02:20–03:45 (marginal, 1.42 h)	79.2° 08:05	4.59	82%	61.7°
2045-07-04 Tue	13	—	unknown	02:15–03:45 (marginal, 1.5 h)	79.2° 08:05	4.62	74%	50.4°
2045-07-05 Wed	14	—	unknown	02:10–03:50 (marginal, 1.67 h)	79.2° 08:00	4.65	65%	39.2°
2045-07-06 Thu	17	—	unknown	02:00–03:50 (marginal, 1.83 h)	79.2° 07:55	4.68	55%	28.3°
2045-07-07 Fri	21	—	unknown	02:50–03:50 (good, 1.0 h)	79.2° 07:50	4.71	45%	18.8°
2045-07-08 Sat	27	—	unknown	02:40–03:50 (good, 1.17 h)	79.2° 07:45	4.74	35%	14.5°
2045-07-09 Sun	33	—	unknown	02:25–03:50 (good, 1.42 h)	79.2° 07:45	4.78	26%	19.9°
2045-07-10 Mon	40	—	unknown	02:10–03:55 (good, 1.75 h)	79.2° 07:40	4.81	17%	30.8°
2045-07-11 Tue	46	—	unknown	02:10–03:55 (good, 1.75 h)	79.2° 07:35	4.85	9%	43.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2045-06-12&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.