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: 01-04 (100), 01-05 (100), 01-06 (100), 01-07 (100), 01-08 (100) — by astronomy; check the weather when the night is within four days.

2038-01-04astronomy score per night — click a bar for that night2038-02-02

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2038-01-04 Mon	100	—	unknown	18:45–00:30 (good, 5.75 h)	79.2° 19:00	11.41	0%	114.4°
2038-01-05 Tue	100	—	unknown	18:45–00:30 (good, 5.75 h)	79.2° 18:55	11.4	0%	102.4°
2038-01-06 Wed	100	—	unknown	18:50–00:25 (good, 5.58 h)	79.2° 18:50	11.39	2%	90.5°
2038-01-07 Thu	100	—	unknown	18:50–00:20 (good, 5.5 h)	79.2° 18:50	11.37	6%	78.9°
2038-01-08 Fri	100	—	unknown	18:50–00:15 (good, 5.42 h)	79.2° 18:45	11.36	12%	67.6°
2038-01-09 Sat	99	—	unknown	18:50–00:10 (good, 5.33 h)	79.2° 18:40	11.34	18%	56.8°
2038-01-10 Sun	91	—	unknown	18:50–00:10 (good, 5.33 h)	79.2° 18:35	11.32	26%	46.6°
2038-01-11 Mon	83	—	unknown	18:50–00:05 (good, 5.25 h)	79.2° 18:30	11.3	35%	37.3°
2038-01-12 Tue	72	—	unknown	18:55–23:40 (good, 4.75 h)	79.2° 18:30	11.28	44%	29.7°
2038-01-13 Wed	55	—	unknown	18:55–22:25 (good, 3.5 h)	79.2° 18:25	11.27	54%	25.1°
2038-01-14 Thu	40	—	unknown	18:55–00:15 (marginal, 5.33 h)	79.2° 18:20	11.24	63%	25.3°
2038-01-15 Fri	29	—	unknown	18:55–23:55 (marginal, 5.0 h)	79.2° 18:15	11.22	72%	30.4°
2038-01-16 Sat	26	—	unknown	18:55–23:45 (marginal, 4.83 h)	79.2° 18:10	11.2	81%	38.8°
2038-01-17 Sun	27	—	unknown	19:00–23:35 (marginal, 4.58 h)	79.2° 18:10	11.18	88%	49.0°
2038-01-18 Mon	32	—	unknown	19:00–23:30 (marginal, 4.5 h)	79.2° 18:05	11.15	94%	60.2°
2038-01-19 Tue	41	—	unknown	19:00–19:35 (good, 0.58 h)	79.2° 18:00	11.13	98%	72.3°
2038-01-20 Wed	55	—	unknown	19:00–21:15 (good, 2.25 h)	79.2° 17:55	11.11	100%	84.8°
2038-01-21 Thu	71	—	unknown	19:00–22:35 (good, 3.58 h)	79.2° 17:55	11.08	99%	97.7°
2038-01-22 Fri	86	—	unknown	19:05–23:00 (good, 3.92 h)	79.2° 17:50	11.05	96%	110.6°
2038-01-23 Sat	100	—	unknown	19:05–23:05 (good, 4.0 h)	79.2° 17:45	11.03	90%	123.4°
2038-01-24 Sun	100	—	unknown	19:05–23:05 (good, 4.0 h)	79.2° 17:40	11.0	82%	135.6°
2038-01-25 Mon	100	—	unknown	19:05–23:05 (good, 4.0 h)	79.2° 17:35	10.97	72%	146.3°
2038-01-26 Tue	100	—	unknown	19:10–23:05 (good, 3.92 h)	79.2° 17:35	10.94	61%	153.8°
2038-01-27 Wed	100	—	unknown	19:10–23:00 (good, 3.83 h)	79.2° 17:30	10.91	50%	155.1°
2038-01-28 Thu	99	—	unknown	19:10–22:55 (good, 3.75 h)	79.2° 17:25	10.88	39%	149.7°
2038-01-29 Fri	97	—	unknown	19:10–22:55 (good, 3.75 h)	79.2° 17:20	10.85	28%	140.4°
2038-01-30 Sat	96	—	unknown	19:10–22:50 (good, 3.67 h)	79.2° 17:15	10.82	19%	129.4°
2038-01-31 Sun	93	—	unknown	19:15–22:45 (good, 3.5 h)	79.2° 17:15	10.79	11%	117.8°
2038-02-01 Mon	91	—	unknown	19:15–22:40 (good, 3.42 h)	79.2° 17:10	10.75	6%	106.1°
2038-02-02 Tue	88	—	unknown	19:15–22:40 (good, 3.42 h)	79.2° 17:05	10.72	2%	94.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2038-01-04&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.