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: 08-03 (100), 08-04 (100), 08-05 (100), 08-06 (100), 08-07 (100) — by astronomy; check the weather when the night is within four days.

2043-07-29astronomy score per night — click a bar for that night2043-08-27

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-07-29 Wed	49	—	unknown	01:20–04:20 (good, 3.0 h)	79.2° 06:25	5.68	43%	19.3°
2043-07-30 Thu	63	—	unknown	01:10–04:20 (good, 3.17 h)	79.2° 06:25	5.73	32%	29.0°
2043-07-31 Fri	79	—	unknown	00:50–04:25 (good, 3.58 h)	79.2° 06:20	5.79	22%	41.4°
2043-08-01 Sat	91	—	unknown	00:45–04:25 (good, 3.67 h)	79.2° 06:15	5.84	13%	54.7°
2043-08-02 Sun	99	—	unknown	00:45–04:25 (good, 3.67 h)	79.2° 06:10	5.9	6%	68.3°
2043-08-03 Mon	100	—	unknown	00:40–04:30 (good, 3.83 h)	79.2° 06:05	5.95	2%	81.9°
2043-08-04 Tue	100	—	unknown	00:35–04:30 (good, 3.92 h)	79.2° 06:05	6.01	0%	95.4°
2043-08-05 Wed	100	—	unknown	00:30–04:30 (good, 4.0 h)	79.2° 06:00	6.06	1%	108.5°
2043-08-06 Thu	100	—	unknown	00:30–04:35 (good, 4.08 h)	79.2° 05:55	6.12	4%	121.3°
2043-08-07 Fri	100	—	unknown	00:25–04:35 (good, 4.17 h)	79.2° 05:50	6.18	9%	133.5°
2043-08-08 Sat	100	—	unknown	00:20–04:35 (good, 4.25 h)	79.2° 05:45	6.23	16%	145.0°
2043-08-09 Sun	100	—	unknown	00:15–04:40 (good, 4.42 h)	79.2° 05:45	6.29	24%	155.1°
2043-08-10 Mon	100	—	unknown	00:10–04:40 (good, 4.5 h)	79.2° 05:40	6.35	33%	162.2°
2043-08-11 Tue	100	—	unknown	00:10–04:40 (good, 4.5 h)	79.2° 05:35	6.41	42%	162.7°
2043-08-12 Wed	100	—	unknown	00:05–04:45 (good, 4.67 h)	79.2° 05:30	6.46	51%	156.4°
2043-08-13 Thu	100	—	unknown	00:05–04:45 (good, 4.67 h)	79.2° 05:30	6.52	61%	147.0°
2043-08-14 Fri	100	—	unknown	00:00–04:45 (good, 4.75 h)	79.2° 05:25	6.58	70%	136.4°
2043-08-15 Sat	100	—	unknown	00:00–04:45 (good, 4.75 h)	79.2° 05:20	6.64	78%	125.3°
2043-08-16 Sun	100	—	unknown	00:00–04:50 (good, 4.83 h)	79.2° 05:15	6.69	86%	113.7°
2043-08-17 Mon	100	—	unknown	00:05–04:50 (good, 4.75 h)	79.2° 05:10	6.75	92%	101.8°
2043-08-18 Tue	100	—	unknown	00:15–04:50 (good, 4.58 h)	79.2° 05:10	6.81	97%	89.6°
2043-08-19 Wed	69	—	unknown	01:35–04:55 (good, 3.33 h)	79.2° 05:05	6.87	99%	77.1°
2043-08-20 Thu	51	—	unknown	04:10–04:55 (good, 0.75 h)	79.2° 05:00	6.92	100%	64.3°
2043-08-21 Fri	37	—	unknown	23:20–04:55 (marginal, 5.58 h)	79.2° 04:55	6.98	98%	51.5°
2043-08-22 Sat	26	—	unknown	23:20–05:00 (marginal, 5.67 h)	79.2° 04:50	7.04	94%	38.8°
2043-08-23 Sun	25	—	unknown	23:15–05:00 (marginal, 5.75 h)	79.2° 04:50	7.1	87%	26.9°
2043-08-24 Mon	33	—	unknown	23:00–05:00 (marginal, 6.0 h)	79.2° 04:45	7.15	78%	18.0°
2043-08-25 Tue	46	—	unknown	22:45–05:00 (marginal, 6.25 h)	79.2° 04:40	7.21	68%	17.7°
2043-08-26 Wed	64	—	unknown	23:40–03:40 (good, 4.0 h)	79.2° 04:35	7.27	57%	26.3°
2043-08-27 Thu	81	—	unknown	23:05–05:05 (good, 6.0 h)	79.2° 04:35	7.32	46%	38.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-07-29&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.