Scores are estimated from moon phase, moonlight interference and dark-window timing for Matsu. This first version does not include cloud cover, so always check weather.
馃寣 Aug is a good window for the Milky Way core over Matsu: it climbs to a shootable altitude around 19:59, sinks back down near 00:19, and peaks around 20:09 at roughly 35掳 in the South. Avoid moonlight and face that direction to catch the bright galactic center.
| Date | Score | Tonight's Moon | Dark window |
|---|---|---|---|
| 2026-08-09 | 92 路 Good | Waning Crescent 17% | 20:06-04:05 |
| 2026-08-10 | 92 路 Good | Waning Crescent 9% | 20:05-04:06 |
| 2026-08-11 | 92 路 Good | Waning Crescent 3% | 20:04-04:06 |
| 2026-08-12 | 92 路 Good | Waning Crescent 0% | 20:03-04:07 |
| 2026-08-13 | 92 路 Good | New Moon 0% | 20:02-04:08 |
| Date | Score | Tonight's Moon | Moonrise | Moonset | Dark window |
|---|---|---|---|---|---|
| 2026-08-01 | 40 路 Poor | Waning Gibbous 94% | 20:25 | 07:33 | 20:13-03:59 |
| 2026-08-02 | 40 路 Poor | Waning Gibbous 88% | 20:56 | 08:29 | 20:12-04:00 |
| 2026-08-03 | 52 路 Fair | Waning Gibbous 80% | 21:27 | 09:25 | 20:11-04:01 |
| 2026-08-04 | 52 路 Fair | Waning Gibbous 71% | 22:00 | 10:23 | 20:10-04:01 |
| 2026-08-05 | 64 路 Fair | Waning Gibbous 60% | 22:38 | 11:23 | 20:09-04:02 |
| 2026-08-06 | 74 路 Fair | Last Quarter 49% | 23:21 | 12:27 | 20:08-04:03 |
| 2026-08-07 | 84 路 Good | Waning Crescent 38% | -- | 13:34 | 20:07-04:04 |
| 2026-08-08 | 84 路 Good | Waning Crescent 27% | 00:11 | 14:43 | 20:06-04:04 |
| 2026-08-09 | 92 路 Good | Waning Crescent 17% | 01:11 | 15:48 | 20:06-04:05 |
| 2026-08-10 | 92 路 Good | Waning Crescent 9% | 02:17 | 16:48 | 20:05-04:06 |
| 2026-08-11 | 92 路 Good | Waning Crescent 3% | 03:28 | 17:40 | 20:04-04:06 |
| 2026-08-12 | 92 路 Good | Waning Crescent 0% | 04:38 | 18:25 | 20:03-04:07 |
| 2026-08-13 | 92 路 Good | New Moon 0% | 05:46 | 19:04 | 20:02-04:08 |
| 2026-08-14 | 92 路 Good | Waxing Crescent 3% | 06:50 | 19:39 | 20:00-04:09 |
| 2026-08-15 | 92 路 Good | Waxing Crescent 8% | 07:51 | 20:11 | 19:59-04:09 |
| 2026-08-16 | 92 路 Good | Waxing Crescent 14% | 08:49 | 20:43 | 19:58-04:10 |
| 2026-08-17 | 84 路 Good | Waxing Crescent 22% | 09:46 | 21:15 | 19:57-04:11 |
| 2026-08-18 | 84 路 Good | Waxing Crescent 31% | 10:43 | 21:50 | 19:56-04:11 |
| 2026-08-19 | 74 路 Fair | Waxing Crescent 41% | 11:40 | 22:27 | 19:55-04:12 |
| 2026-08-20 | 64 路 Fair | First Quarter 50% | 12:37 | 23:08 | 19:54-04:13 |
| 2026-08-21 | 64 路 Fair | Waxing Gibbous 60% | 13:33 | 23:54 | 19:53-04:13 |
| 2026-08-22 | 62 路 Fair | Waxing Gibbous 69% | 14:26 | -- | 19:52-04:14 |
| 2026-08-23 | 62 路 Fair | Waxing Gibbous 77% | 15:17 | 00:45 | 19:51-04:14 |
| 2026-08-24 | 52 路 Fair | Waxing Gibbous 85% | 16:03 | 01:39 | 19:49-04:15 |
| 2026-08-25 | 40 路 Poor | Waxing Gibbous 91% | 16:44 | 02:35 | 19:48-04:16 |
| 2026-08-26 | 40 路 Poor | Waxing Gibbous 96% | 17:21 | 03:32 | 19:47-04:16 |
| 2026-08-27 | 40 路 Poor | Waxing Gibbous 99% | 17:55 | 04:29 | 19:46-04:17 |
| 2026-08-28 | 40 路 Poor | Full Moon 100% | 18:27 | 05:26 | 19:45-04:18 |
| 2026-08-29 | 40 路 Poor | Waning Gibbous 99% | 18:58 | 06:22 | 19:44-04:18 |
| 2026-08-30 | 40 路 Poor | Waning Gibbous 96% | 19:29 | 07:19 | 19:42-04:19 |
| 2026-08-31 | 40 路 Poor | Waning Gibbous 90% | 20:02 | 08:17 | 19:41-04:19 |
The Matsu calendar combines Moon phase, dark windows, and short-range conditions, but the score still needs local context and light pollution checks.
Score
High scores mean friendlier moonlight and night windows, and short-range views can include cloud and transparency. Local fog, patchy cloud, and nearby lights can still change the outcome.
Moonlight
Full-moon periods light the landscape but reduce faint-star and Milky Way contrast. For the Milky Way, meteors, or deep-sky targets, new-moon periods are usually better.
Dark window
Dark outside is not always dark enough. The dark window considers twilight ending, Moon rise and set, and the length of usable night.
After choosing a good date, confirm location, direction, and hourly weather for the night.
Short range
Moon phase can be planned months ahead, but cloud needs a short-range forecast. For the actual night, use hourly stargazing index and on-site observation.
Place
High elevation may help with low cloud, but nearby lights can still wash out the sky. Use the dark-sky map to remove weak candidates first.
Direction
A site may only work for certain horizons. Use the sky map to check the galactic center, Moon, and constellations before facing sea, mountains, or city lights.
Related tools: Stargazing & Moon Viewing Score 路 This month鈥檚 Moon phase calendar 路 Astro Events 路 Meteor Showers