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: 01-23 (94), 01-24 (85), 02-05 (77), 02-06 (77), 02-07 (76) — by astronomy; check the weather when the night is within four days.

2034-01-23astronomy score per night — click a bar for that night2034-02-21

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-01-23 Mon	94	—	unknown	19:05–23:15 (good, 4.17 h)	79.1° 17:45	11.03	15%	46.6°
2034-01-24 Tue	85	—	unknown	19:05–23:15 (good, 4.17 h)	79.1° 17:40	11.0	24%	35.0°
2034-01-25 Wed	68	—	unknown	19:05–22:55 (good, 3.83 h)	79.1° 17:35	10.97	34%	25.7°
2034-01-26 Thu	51	—	unknown	19:10–22:40 (good, 3.5 h)	79.1° 17:35	10.94	45%	21.7°
2034-01-27 Fri	36	—	unknown	19:10–23:25 (marginal, 4.25 h)	79.1° 17:30	10.91	57%	25.8°
2034-01-28 Sat	27	—	unknown	19:10–23:10 (marginal, 4.0 h)	79.1° 17:25	10.88	68%	35.1°
2034-01-29 Sun	25	—	unknown	19:10–23:00 (marginal, 3.83 h)	79.1° 17:20	10.85	78%	46.6°
2034-01-30 Mon	27	—	unknown	19:10–22:55 (marginal, 3.75 h)	79.1° 17:15	10.82	86%	58.8°
2034-01-31 Tue	32	—	unknown	18:40–22:55 (marginal, 4.25 h)	79.1° 17:15	10.79	93%	71.3°
2034-02-01 Wed	40	—	unknown	19:15–20:30 (good, 1.25 h)	79.1° 17:10	10.76	97%	83.8°
2034-02-02 Thu	50	—	unknown	19:15–21:35 (good, 2.33 h)	79.1° 17:05	10.72	100%	96.2°
2034-02-03 Fri	61	—	unknown	19:15–22:10 (good, 2.92 h)	79.1° 17:00	10.69	100%	108.3°
2034-02-04 Sat	70	—	unknown	19:20–22:20 (good, 3.0 h)	79.1° 16:55	10.65	98%	120.0°
2034-02-05 Sun	77	—	unknown	19:20–22:15 (good, 2.92 h)	79.1° 16:55	10.62	94%	131.1°
2034-02-06 Mon	77	—	unknown	19:20–22:15 (good, 2.92 h)	79.1° 16:50	10.58	88%	141.5°
2034-02-07 Tue	76	—	unknown	19:20–22:10 (good, 2.83 h)	79.1° 16:45	10.55	81%	150.4°
2034-02-08 Wed	75	—	unknown	19:20–22:15 (good, 2.92 h)	79.1° 16:40	10.51	73%	156.6°
2034-02-09 Thu	71	—	unknown	19:25–22:10 (good, 2.75 h)	79.1° 16:40	10.47	64%	157.9°
2034-02-10 Fri	69	—	unknown	19:25–22:05 (good, 2.67 h)	79.1° 16:35	10.44	55%	153.6°
2034-02-11 Sat	67	—	unknown	19:25–22:00 (good, 2.58 h)	79.1° 16:30	10.4	46%	145.8°
2034-02-12 Sun	65	—	unknown	19:25–22:00 (good, 2.58 h)	79.1° 16:25	10.36	36%	136.1°
2034-02-13 Mon	62	—	unknown	19:30–21:55 (good, 2.42 h)	79.1° 16:20	10.32	27%	125.4°
2034-02-14 Tue	60	—	unknown	19:30–21:50 (good, 2.33 h)	79.1° 16:20	10.28	18%	114.0°
2034-02-15 Wed	57	—	unknown	19:30–21:45 (good, 2.25 h)	79.1° 16:15	10.24	11%	102.0°
2034-02-16 Thu	55	—	unknown	19:30–21:45 (good, 2.25 h)	79.1° 16:10	10.2	5%	89.6°
2034-02-17 Fri	53	—	unknown	19:30–21:40 (good, 2.17 h)	79.1° 16:05	10.16	2%	76.8°
2034-02-18 Sat	51	—	unknown	19:35–21:35 (good, 2.0 h)	79.1° 16:00	10.12	0%	63.8°
2034-02-19 Sun	49	—	unknown	19:35–21:30 (good, 1.92 h)	79.1° 16:00	10.08	1%	50.9°
2034-02-20 Mon	45	—	unknown	19:35–21:25 (good, 1.83 h)	79.1° 15:55	10.04	5%	38.6°
2034-02-21 Tue	40	—	unknown	19:35–21:25 (good, 1.83 h)	79.1° 15:50	10.0	12%	28.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-01-23&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.