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: 09-08 (100), 09-09 (100), 09-10 (100), 09-11 (100), 09-12 (100) — by astronomy; check the weather when the night is within four days.

2043-09-08astronomy score per night — click a bar for that night2043-10-07

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-09-08 Tue	100	—	unknown	22:20–05:20 (good, 7.0 h)	79.2° 03:45	7.99	26%	159.1°
2043-09-09 Wed	100	—	unknown	22:15–05:20 (good, 7.08 h)	79.2° 03:40	8.05	35%	150.4°
2043-09-10 Thu	100	—	unknown	22:15–05:25 (good, 7.17 h)	79.2° 03:40	8.1	44%	140.2°
2043-09-11 Fri	100	—	unknown	22:10–05:25 (good, 7.25 h)	79.2° 03:35	8.15	54%	129.3°
2043-09-12 Sat	100	—	unknown	22:10–05:25 (good, 7.25 h)	79.2° 03:30	8.21	63%	118.0°
2043-09-13 Sun	100	—	unknown	22:10–05:25 (good, 7.25 h)	79.2° 03:25	8.26	72%	106.3°
2043-09-14 Mon	100	—	unknown	22:15–05:30 (good, 7.25 h)	79.2° 03:20	8.31	81%	94.3°
2043-09-15 Tue	100	—	unknown	22:40–05:30 (good, 6.83 h)	79.2° 03:20	8.37	88%	82.0°
2043-09-16 Wed	100	—	unknown	00:20–05:30 (good, 5.17 h)	79.2° 03:15	8.42	94%	69.3°
2043-09-17 Thu	67	—	unknown	04:00–05:30 (good, 1.5 h)	79.2° 03:10	8.47	98%	56.4°
2043-09-18 Fri	49	—	unknown	21:40–05:35 (marginal, 7.92 h)	79.2° 03:05	8.52	100%	43.4°
2043-09-19 Sat	29	—	unknown	21:40–01:30 (marginal, 3.83 h)	79.2° 03:00	8.57	99%	30.8°
2043-09-20 Sun	28	—	unknown	21:25–01:55 (marginal, 4.5 h)	79.2° 03:00	8.63	95%	20.2°
2043-09-21 Mon	36	—	unknown	21:15–05:35 (marginal, 8.33 h)	79.2° 02:55	8.68	89%	16.6°
2043-09-22 Tue	50	—	unknown	20:55–05:40 (marginal, 8.75 h)	79.2° 02:50	8.73	81%	23.6°
2043-09-23 Wed	77	—	unknown	23:15–00:35 (good, 1.33 h)	79.2° 02:45	8.78	71%	35.2°
2043-09-24 Thu	85	—	unknown	21:15–05:20 (good, 8.08 h)	79.2° 02:45	8.83	60%	48.1°
2043-09-25 Fri	93	—	unknown	21:10–05:40 (good, 8.5 h)	79.2° 02:40	8.88	48%	61.3°
2043-09-26 Sat	100	—	unknown	21:05–05:45 (good, 8.67 h)	79.2° 02:35	8.93	37%	74.5°
2043-09-27 Sun	100	—	unknown	21:05–05:45 (good, 8.67 h)	79.2° 02:30	8.98	27%	87.6°
2043-09-28 Mon	100	—	unknown	21:00–05:45 (good, 8.75 h)	79.2° 02:25	9.03	18%	100.5°
2043-09-29 Tue	100	—	unknown	20:55–05:45 (good, 8.83 h)	79.2° 02:25	9.08	10%	113.1°
2043-09-30 Wed	100	—	unknown	20:50–05:45 (good, 8.92 h)	79.2° 02:20	9.13	5%	125.4°
2043-10-01 Thu	100	—	unknown	20:50–05:50 (good, 9.0 h)	79.2° 02:15	9.17	2%	137.3°
2043-10-02 Fri	100	—	unknown	20:45–05:50 (good, 9.08 h)	79.2° 02:10	9.22	0%	148.4°
2043-10-03 Sat	100	—	unknown	20:40–05:50 (good, 9.17 h)	79.2° 02:05	9.27	1%	157.9°
2043-10-04 Sun	100	—	unknown	20:35–05:50 (good, 9.25 h)	79.2° 02:05	9.32	3%	163.4°
2043-10-05 Mon	100	—	unknown	20:30–05:55 (good, 9.42 h)	79.2° 02:00	9.36	7%	161.2°
2043-10-06 Tue	100	—	unknown	20:30–05:55 (good, 9.42 h)	79.2° 01:55	9.41	13%	153.5°
2043-10-07 Wed	100	—	unknown	20:30–05:55 (good, 9.42 h)	79.2° 01:50	9.46	20%	143.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-09-08&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.