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: 07-31 (96), 07-30 (93), 07-29 (91), 07-28 (86), 07-27 (78) — by astronomy; check the weather when the night is within four days.

2038-07-02astronomy score per night — click a bar for that night2038-07-31

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
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°
2038-07-24 Sat	46	—	unknown	01:35–04:15 (good, 2.67 h)	79.2° 06:45	5.43	43%	24.8°
2038-07-25 Sun	57	—	unknown	01:15–04:15 (good, 3.0 h)	79.2° 06:40	5.48	34%	29.5°
2038-07-26 Mon	67	—	unknown	01:10–04:15 (good, 3.08 h)	79.2° 06:35	5.53	25%	37.5°
2038-07-27 Tue	78	—	unknown	01:05–04:20 (good, 3.25 h)	79.2° 06:35	5.58	17%	47.1°
2038-07-28 Wed	86	—	unknown	01:00–04:20 (good, 3.33 h)	79.2° 06:30	5.64	10%	57.8°
2038-07-29 Thu	91	—	unknown	01:00–04:20 (good, 3.33 h)	79.2° 06:25	5.69	5%	69.2°
2038-07-30 Fri	93	—	unknown	00:55–04:20 (good, 3.42 h)	79.2° 06:20	5.74	1%	81.1°
2038-07-31 Sat	96	—	unknown	00:50–04:25 (good, 3.58 h)	79.2° 06:20	5.8	0%	93.4°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2038-07-02&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.