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: 02-12 (63), 02-13 (63), 02-14 (60), 02-15 (58), 02-11 (57) — by astronomy; check the weather when the night is within four days.

2028-02-10astronomy score per night — click a bar for that night2028-03-10

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2028-02-10 Thu	51	—	unknown	19:25–21:50 (good, 2.42 h)	79.1° 16:35	10.46	100%	112.3°
2028-02-11 Fri	57	—	unknown	19:25–21:55 (good, 2.5 h)	79.1° 16:30	10.42	97%	127.0°
2028-02-12 Sat	63	—	unknown	19:25–21:50 (good, 2.42 h)	79.1° 16:30	10.38	92%	141.1°
2028-02-13 Sun	63	—	unknown	19:25–21:55 (good, 2.5 h)	79.1° 16:25	10.34	84%	154.2°
2028-02-14 Mon	60	—	unknown	19:30–21:50 (good, 2.33 h)	79.1° 16:20	10.3	75%	164.0°
2028-02-15 Tue	58	—	unknown	19:30–21:50 (good, 2.33 h)	79.1° 16:15	10.27	65%	164.6°
2028-02-16 Wed	56	—	unknown	19:30–21:45 (good, 2.25 h)	79.1° 16:10	10.23	54%	156.0°
2028-02-17 Thu	55	—	unknown	19:30–21:40 (good, 2.17 h)	79.1° 16:10	10.18	44%	144.8°
2028-02-18 Fri	51	—	unknown	19:35–21:35 (good, 2.0 h)	79.1° 16:05	10.14	34%	133.1°
2028-02-19 Sat	49	—	unknown	19:35–21:30 (good, 1.92 h)	79.1° 16:00	10.1	25%	121.3°
2028-02-20 Sun	47	—	unknown	19:35–21:30 (good, 1.92 h)	79.1° 15:55	10.06	17%	109.6°
2028-02-21 Mon	46	—	unknown	19:35–21:25 (good, 1.83 h)	79.1° 15:50	10.02	10%	98.0°
2028-02-22 Tue	44	—	unknown	19:35–21:20 (good, 1.75 h)	79.1° 15:50	9.98	6%	86.5°
2028-02-23 Wed	41	—	unknown	19:40–21:15 (good, 1.58 h)	79.1° 15:45	9.93	2%	75.0°
2028-02-24 Thu	39	—	unknown	19:40–21:15 (good, 1.58 h)	79.1° 15:40	9.89	0%	63.6°
2028-02-25 Fri	38	—	unknown	19:40–21:10 (good, 1.5 h)	79.1° 15:35	9.85	0%	52.3°
2028-02-26 Sat	36	—	unknown	19:40–21:05 (good, 1.42 h)	79.1° 15:35	9.8	2%	41.1°
2028-02-27 Sun	32	—	unknown	19:45–21:00 (good, 1.25 h)	79.1° 15:30	9.76	6%	30.3°
2028-02-28 Mon	28	—	unknown	19:45–20:55 (good, 1.17 h)	79.1° 15:25	9.71	11%	20.5°
2028-02-29 Tue	24	—	unknown	19:45–20:45 (good, 1.0 h)	79.1° 15:20	9.67	18%	14.5°
2028-03-01 Wed	20	—	unknown	19:45–20:35 (good, 0.83 h)	79.1° 15:15	9.62	26%	17.1°
2028-03-02 Thu	15	—	unknown	19:50–20:20 (good, 0.5 h)	79.1° 15:15	9.58	35%	26.2°
2028-03-03 Fri	12	—	unknown	19:50–21:05 (marginal, 1.25 h)	79.1° 15:10	9.53	45%	37.6°
2028-03-04 Sat	9	—	unknown	19:50–21:00 (marginal, 1.17 h)	79.1° 15:05	9.48	56%	50.0°
2028-03-05 Sun	9	—	unknown	19:50–20:50 (marginal, 1.0 h)	79.1° 15:00	9.44	67%	63.2°
2028-03-06 Mon	8	—	unknown	19:55–20:50 (marginal, 0.92 h)	79.1° 14:55	9.39	77%	76.8°
2028-03-07 Tue	9	—	unknown	19:55–20:50 (marginal, 0.92 h)	79.1° 14:55	9.34	86%	91.0°
2028-03-08 Wed	10	—	unknown	19:55–20:00 (good, 0.08 h)	79.1° 14:50	9.29	93%	105.4°
2028-03-09 Thu	11	—	unknown	19:55–20:05 (good, 0.17 h)	79.1° 14:45	9.25	98%	120.0°
2028-03-10 Fri	10	—	unknown	19:55–20:05 (good, 0.17 h)	79.1° 14:40	9.2	100%	134.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2028-02-10&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.