Scores are estimated from moon phase, moonlight interference and dark-window timing for Honolulu. This first version does not include cloud cover, so always check weather.
🌌 Sep is a good window for the Milky Way core over Honolulu: it climbs to a shootable altitude around 19:49, sinks back down near 22:59, and peaks around 19:49 at roughly 37° in the South. Avoid moonlight and face that direction to catch the bright galactic center.
That is where the core sits in the sky over Honolulu — not a promise you can see it. Under city lights it is essentially invisible, and our dark-sky catalogue currently lists no qualifying site in the region around Honolulu.
| Date | Score | Tonight's Moon | Dark window |
|---|---|---|---|
| 2026-09-07 | 92 · Good | Waning Crescent 13% | 19:57-05:01 |
| 2026-09-08 | 92 · Good | Waning Crescent 6% | 19:56-05:01 |
| 2026-09-09 | 92 · Good | Waning Crescent 2% | 19:55-05:01 |
| 2026-09-10 | 92 · Good | New Moon 0% | 19:54-05:02 |
| 2026-09-11 | 92 · Good | Waxing Crescent 1% | 19:53-05:02 |
| Date | Score | Tonight's Moon | Moonrise | Moonset | Dark window |
|---|---|---|---|---|---|
| 2026-09-01 | 52 · Fair | Waning Gibbous 76% | 21:50 | 10:29 | 20:03-04:58 |
| 2026-09-02 | 52 · Fair | Waning Gibbous 66% | 22:38 | 11:32 | 20:02-04:59 |
| 2026-09-03 | 74 · Fair | Last Quarter 55% | 23:33 | 12:37 | 20:01-04:59 |
| 2026-09-04 | 74 · Fair | Waning Crescent 43% | -- | 13:42 | 20:00-05:00 |
| 2026-09-05 | 84 · Good | Waning Crescent 32% | 00:35 | 14:44 | 19:59-05:00 |
| 2026-09-06 | 84 · Good | Waning Crescent 22% | 01:40 | 15:41 | 19:58-05:00 |
| 2026-09-07 | 92 · Good | Waning Crescent 13% | 02:47 | 16:31 | 19:57-05:01 |
| 2026-09-08 | 92 · Good | Waning Crescent 6% | 03:52 | 17:15 | 19:56-05:01 |
| 2026-09-09 | 92 · Good | Waning Crescent 2% | 04:55 | 17:54 | 19:55-05:01 |
| 2026-09-10 | 92 · Good | New Moon 0% | 05:54 | 18:31 | 19:54-05:02 |
| 2026-09-11 | 92 · Good | Waxing Crescent 1% | 06:51 | 19:06 | 19:53-05:02 |
| 2026-09-12 | 92 · Good | Waxing Crescent 4% | 07:47 | 19:41 | 19:52-05:02 |
| 2026-09-13 | 92 · Good | Waxing Crescent 9% | 08:42 | 20:16 | 19:51-05:03 |
| 2026-09-14 | 92 · Good | Waxing Crescent 15% | 09:37 | 20:54 | 19:50-05:03 |
| 2026-09-15 | 84 · Good | Waxing Crescent 23% | 10:33 | 21:36 | 19:49-05:03 |
| 2026-09-16 | 84 · Good | Waxing Crescent 32% | 11:28 | 22:20 | 19:48-05:03 |
| 2026-09-17 | 74 · Fair | Waxing Crescent 41% | 12:23 | 23:09 | 19:47-05:04 |
| 2026-09-18 | 74 · Fair | First Quarter 50% | 13:15 | -- | 19:46-05:04 |
| 2026-09-19 | 74 · Fair | Waxing Gibbous 60% | 14:04 | 00:01 | 19:45-05:04 |
| 2026-09-20 | 62 · Fair | Waxing Gibbous 69% | 14:50 | 00:55 | 19:43-05:05 |
| 2026-09-21 | 52 · Fair | Waxing Gibbous 78% | 15:31 | 01:50 | 19:42-05:05 |
| 2026-09-22 | 40 · Poor | Waxing Gibbous 85% | 16:09 | 02:44 | 19:41-05:05 |
| 2026-09-23 | 40 · Poor | Waxing Gibbous 92% | 16:45 | 03:39 | 19:40-05:05 |
| 2026-09-24 | 40 · Poor | Waxing Gibbous 96% | 17:19 | 04:33 | 19:39-05:06 |
| 2026-09-25 | 40 · Poor | Waxing Gibbous 99% | 17:53 | 05:27 | 19:38-05:06 |
| 2026-09-26 | 40 · Poor | Full Moon 100% | 18:29 | 06:22 | 19:37-05:06 |
| 2026-09-27 | 40 · Poor | Waning Gibbous 98% | 19:06 | 07:20 | 19:36-05:07 |
| 2026-09-28 | 40 · Poor | Waning Gibbous 94% | 19:48 | 08:20 | 19:35-05:07 |
| 2026-09-29 | 40 · Poor | Waning Gibbous 87% | 20:35 | 09:23 | 19:35-05:07 |
| 2026-09-30 | 52 · Fair | Waning Gibbous 79% | 21:29 | 10:29 | 19:34-05:07 |
The Honolulu 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 · This month’s Moon phase calendar · Astronomy Calendar · Meteor Showers