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 Seven Sisters: 03-02 (74), 03-03 (71), 03-04 (69), 03-05 (67), 03-06 (65) — by astronomy; check the weather when the night is within four days.

2038-03-02astronomy score per night — click a bar for that night2038-03-31

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2038-03-02 Tue	74	—	unknown	19:45–22:40 (good, 2.92 h)	72.5° 17:30	9.6	9%	111.5°
2038-03-03 Wed	71	—	unknown	19:50–22:35 (good, 2.75 h)	72.5° 17:25	9.55	4%	99.2°
2038-03-04 Thu	69	—	unknown	19:50–22:30 (good, 2.67 h)	72.5° 17:20	9.5	1%	87.1°
2038-03-05 Fri	67	—	unknown	19:50–22:25 (good, 2.58 h)	72.5° 17:15	9.46	0%	75.1°
2038-03-06 Sat	65	—	unknown	19:50–22:25 (good, 2.58 h)	72.5° 17:10	9.41	1%	63.2°
2038-03-07 Sun	61	—	unknown	19:55–22:20 (good, 2.42 h)	72.5° 17:10	9.36	4%	51.4°
2038-03-08 Mon	56	—	unknown	19:55–22:15 (good, 2.33 h)	72.5° 17:05	9.32	8%	39.8°
2038-03-09 Tue	50	—	unknown	19:55–22:10 (good, 2.25 h)	72.5° 17:00	9.27	14%	28.4°
2038-03-10 Wed	43	—	unknown	19:55–22:00 (good, 2.08 h)	72.5° 16:55	9.22	21%	17.4°
2038-03-11 Thu	35	—	unknown	20:00–21:50 (good, 1.83 h)	72.5° 16:50	9.17	29%	8.6°
2038-03-12 Fri	28	—	unknown	20:00–21:35 (good, 1.58 h)	72.5° 16:50	9.12	38%	11.5°
2038-03-13 Sat	21	—	unknown	20:00–22:20 (marginal, 2.33 h)	72.5° 16:45	9.07	48%	22.1°
2038-03-14 Sun	16	—	unknown	20:00–22:05 (marginal, 2.08 h)	72.5° 16:40	9.02	58%	34.2°
2038-03-15 Mon	13	—	unknown	20:05–22:00 (marginal, 1.92 h)	72.5° 16:35	8.97	68%	46.9°
2038-03-16 Tue	13	—	unknown	20:05–21:55 (marginal, 1.83 h)	72.5° 16:35	8.92	78%	60.2°
2038-03-17 Wed	15	—	unknown	20:05–21:55 (marginal, 1.83 h)	72.5° 16:30	8.87	86%	74.0°
2038-03-18 Thu	18	—	unknown	20:05–20:10 (good, 0.08 h)	72.5° 16:25	8.82	93%	88.3°
2038-03-19 Fri	21	—	unknown	20:10–21:05 (good, 0.92 h)	72.5° 16:20	8.77	98%	103.0°
2038-03-20 Sat	26	—	unknown	20:10–21:15 (good, 1.08 h)	72.5° 16:15	8.72	100%	117.9°
2038-03-21 Sun	26	—	unknown	20:10–21:15 (good, 1.08 h)	72.5° 16:15	8.67	99%	132.9°
2038-03-22 Mon	29	—	unknown	20:10–21:10 (good, 1.0 h)	72.5° 16:10	8.61	95%	147.7°
2038-03-23 Tue	28	—	unknown	20:15–21:15 (good, 1.0 h)	72.5° 16:05	8.56	88%	161.9°
2038-03-24 Wed	27	—	unknown	20:15–21:10 (good, 0.92 h)	72.5° 16:00	8.51	79%	172.0°
2038-03-25 Thu	25	—	unknown	20:15–21:10 (good, 0.92 h)	72.5° 15:55	8.46	69%	165.4°
2038-03-26 Fri	23	—	unknown	20:15–21:05 (good, 0.83 h)	72.5° 15:55	8.4	59%	152.7°
2038-03-27 Sat	22	—	unknown	20:20–21:00 (good, 0.67 h)	72.5° 15:50	8.35	48%	139.7°
2038-03-28 Sun	20	—	unknown	21:20–21:55 (good, 0.58 h)	72.5° 16:45	8.3	38%	127.0°
2038-03-29 Mon	19	—	unknown	21:20–21:50 (good, 0.5 h)	72.5° 16:40	8.24	28%	114.4°
2038-03-30 Tue	17	—	unknown	21:20–21:50 (good, 0.5 h)	72.5° 16:40	8.19	20%	102.1°
2038-03-31 Wed	13	—	unknown	21:25–21:45 (good, 0.33 h)	72.5° 16:35	8.13	12%	90.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2038-03-02&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.