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: 07-13 (49), 07-12 (48), 07-11 (47), 07-10 (46), 07-14 (45) — by astronomy; check the weather when the night is within four days.

2038-06-24astronomy score per night — click a bar for that night2038-07-23

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2038-06-24 Thu	11	—	unknown	02:45–04:30 (marginal, 1.75 h)	79.2° 08:45	4.44	46%	35.0°
2038-06-25 Fri	13	—	unknown	03:30–03:40 (good, 0.17 h)	79.2° 08:40	4.45	37%	27.9°
2038-06-26 Sat	17	—	unknown	03:20–03:40 (good, 0.33 h)	79.2° 08:35	4.46	28%	24.3°
2038-06-27 Sun	20	—	unknown	03:05–03:40 (good, 0.58 h)	79.2° 08:30	4.47	20%	25.9°
2038-06-28 Mon	24	—	unknown	03:00–03:40 (good, 0.67 h)	79.2° 08:25	4.48	13%	31.9°
2038-06-29 Tue	26	—	unknown	02:55–03:40 (good, 0.75 h)	79.2° 08:25	4.5	7%	40.6°
2038-06-30 Wed	28	—	unknown	02:50–03:45 (good, 0.92 h)	79.2° 08:20	4.52	3%	50.7°
2038-07-01 Thu	29	—	unknown	02:50–03:45 (good, 0.92 h)	79.2° 08:15	4.54	0%	61.7°
2038-07-02 Fri	31	—	unknown	02:45–03:45 (good, 1.0 h)	79.2° 08:10	4.56	0%	73.2°
2038-07-03 Sat	33	—	unknown	02:40–03:45 (good, 1.08 h)	79.2° 08:10	4.59	2%	85.1°
2038-07-04 Sun	34	—	unknown	02:35–03:45 (good, 1.17 h)	79.2° 08:05	4.61	6%	97.2°
2038-07-05 Mon	37	—	unknown	02:35–03:50 (good, 1.25 h)	79.2° 08:00	4.64	13%	109.5°
2038-07-06 Tue	38	—	unknown	02:30–03:50 (good, 1.33 h)	79.2° 07:55	4.67	21%	121.7°
2038-07-07 Wed	40	—	unknown	02:25–03:50 (good, 1.42 h)	79.2° 07:50	4.7	31%	133.6°
2038-07-08 Thu	42	—	unknown	02:20–03:50 (good, 1.5 h)	79.2° 07:50	4.73	42%	144.4°
2038-07-09 Fri	43	—	unknown	02:15–03:50 (good, 1.58 h)	79.2° 07:45	4.77	53%	152.8°
2038-07-10 Sat	46	—	unknown	02:15–03:55 (good, 1.67 h)	79.2° 07:40	4.8	64%	155.7°
2038-07-11 Sun	47	—	unknown	02:15–03:55 (good, 1.67 h)	79.2° 07:35	4.84	75%	151.4°
2038-07-12 Mon	48	—	unknown	02:10–03:55 (good, 1.75 h)	79.2° 07:30	4.88	84%	142.1°
2038-07-13 Tue	49	—	unknown	02:10–03:55 (good, 1.75 h)	79.2° 07:30	4.92	92%	130.7°
2038-07-14 Wed	45	—	unknown	02:10–04:00 (good, 1.83 h)	79.2° 07:25	4.96	97%	118.5°
2038-07-15 Thu	40	—	unknown	02:10–04:00 (good, 1.83 h)	79.2° 07:20	5.0	100%	106.0°
2038-07-16 Fri	34	—	unknown	02:15–04:00 (good, 1.75 h)	79.2° 07:15	5.05	100%	93.6°
2038-07-17 Sat	30	—	unknown	03:10–04:05 (good, 0.92 h)	79.2° 07:15	5.09	98%	81.4°
2038-07-18 Sun	26	—	unknown	01:20–04:05 (marginal, 2.75 h)	79.2° 07:10	5.14	93%	69.5°
2038-07-19 Mon	24	—	unknown	01:20–04:05 (marginal, 2.75 h)	79.2° 07:05	5.18	87%	58.2°
2038-07-20 Tue	23	—	unknown	01:15–04:05 (marginal, 2.83 h)	79.2° 07:00	5.23	80%	47.6°
2038-07-21 Wed	25	—	unknown	01:05–04:10 (marginal, 3.08 h)	79.2° 06:55	5.28	71%	37.9°
2038-07-22 Thu	28	—	unknown	01:00–04:10 (marginal, 3.17 h)	79.2° 06:55	5.33	62%	29.9°
2038-07-23 Fri	35	—	unknown	01:55–04:10 (good, 2.25 h)	79.2° 06:50	5.38	53%	24.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2038-06-24&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.