Pick the dates from geometry.
Moon and darkness timing can be calculated ahead; weather becomes less certain further out. Choose the window now and check the cloud when it gets close. Thirty nights at Mauna Kea.
18 Sept · Mauna Kea
First quarter · 56% lit at local midnight.
Astronomical darkness
18 Sept · 19:40 → 19 Sept · 05:00 (9.3h)
Moon below horizon during darkness
4.7h total.
Longest window for your filters
19 Sept · 00:20 → 19 Sept · 05:00 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
19 Sept · Mauna Kea
Waxing gibbous · 65% lit at local midnight.
Astronomical darkness
19 Sept · 19:40 → 20 Sept · 05:00 (9.3h)
Moon below horizon during darkness
4.0h total.
Longest window for your filters
20 Sept · 01:00 → 20 Sept · 05:00 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
20 Sept · Mauna Kea
Waxing gibbous · 73% lit at local midnight.
Astronomical darkness
20 Sept · 19:40 → 21 Sept · 05:00 (9.3h)
Moon below horizon during darkness
3.0h total.
Longest window for your filters
21 Sept · 02:00 → 21 Sept · 05:00 Does not meet your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
21 Sept · Mauna Kea
Waxing gibbous · 81% lit at local midnight.
Astronomical darkness
21 Sept · 19:40 → 22 Sept · 05:00 (9.3h)
Moon below horizon during darkness
2.0h total.
Longest window for your filters
22 Sept · 03:00 → 22 Sept · 05:00 Does not meet your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
22 Sept · Mauna Kea
Waxing gibbous · 88% lit at local midnight.
Astronomical darkness
22 Sept · 19:40 → 23 Sept · 05:00 (9.3h)
Moon below horizon during darkness
1.3h total.
Longest window for your filters
23 Sept · 03:40 → 23 Sept · 05:00 Does not meet your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
23 Sept · Mauna Kea
Waxing gibbous · 94% lit at local midnight.
Astronomical darkness
23 Sept · 19:40 → 24 Sept · 05:00 (9.3h)
Moon below horizon during darkness
0.3h total.
Longest window for your filters
24 Sept · 04:40 → 24 Sept · 05:00 Does not meet your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
24 Sept · Mauna Kea
Waxing gibbous · 98% lit at local midnight.
Astronomical darkness
24 Sept · 19:40 → 25 Sept · 05:00 (9.3h)
Moon below horizon during darkness
0.0h total.
Longest window for your filters
None. Does not meet your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
25 Sept · Mauna Kea
Full moon · 100% lit at local midnight.
Astronomical darkness
25 Sept · 19:40 → 26 Sept · 05:00 (9.3h)
Moon below horizon during darkness
0.0h total.
Longest window for your filters
None. Does not meet your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
26 Sept · Mauna Kea
Full moon · 99% lit at local midnight.
Astronomical darkness
26 Sept · 19:40 → 27 Sept · 05:00 (9.3h)
Moon below horizon during darkness
0.0h total.
Longest window for your filters
None. Does not meet your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
27 Sept · Mauna Kea
Waning gibbous · 97% lit at local midnight.
Astronomical darkness
27 Sept · 19:40 → 28 Sept · 05:00 (9.3h)
Moon below horizon during darkness
0.0h total.
Longest window for your filters
None. Does not meet your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
28 Sept · Mauna Kea
Waning gibbous · 91% lit at local midnight.
Astronomical darkness
28 Sept · 19:40 → 29 Sept · 05:00 (9.3h)
Moon below horizon during darkness
0.0h total.
Longest window for your filters
None. Does not meet your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
29 Sept · Mauna Kea
Waning gibbous · 84% lit at local midnight.
Astronomical darkness
29 Sept · 19:40 → 30 Sept · 05:00 (9.3h)
Moon below horizon during darkness
1.0h total.
Longest window for your filters
29 Sept · 19:40 → 29 Sept · 20:40 Does not meet your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
30 Sept · Mauna Kea
Waning gibbous · 75% lit at local midnight.
Astronomical darkness
30 Sept · 19:40 → 1 Oct · 05:00 (9.3h)
Moon below horizon during darkness
1.7h total.
Longest window for your filters
30 Sept · 19:40 → 30 Sept · 21:20 Does not meet your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
1 Oct · Mauna Kea
Waning gibbous · 64% lit at local midnight.
Astronomical darkness
1 Oct · 19:40 → 2 Oct · 05:20 (9.7h)
Moon below horizon during darkness
2.7h total.
Longest window for your filters
1 Oct · 19:40 → 1 Oct · 22:20 Does not meet your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
2 Oct · Mauna Kea
Last quarter · 52% lit at local midnight.
Astronomical darkness
2 Oct · 19:40 → 3 Oct · 05:20 (9.7h)
Moon below horizon during darkness
4.0h total.
Longest window for your filters
2 Oct · 19:40 → 2 Oct · 23:40 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
3 Oct · Mauna Kea
Last quarter · 40% lit at local midnight.
Astronomical darkness
3 Oct · 19:40 → 4 Oct · 05:20 (9.7h)
Moon below horizon during darkness
5.0h total.
Longest window for your filters
3 Oct · 19:40 → 4 Oct · 00:40 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
4 Oct · Mauna Kea
Waning crescent · 29% lit at local midnight.
Astronomical darkness
4 Oct · 19:40 → 5 Oct · 05:20 (9.7h)
Moon below horizon during darkness
6.0h total.
Longest window for your filters
4 Oct · 19:40 → 5 Oct · 01:40 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
5 Oct · Mauna Kea
Waning crescent · 19% lit at local midnight.
Astronomical darkness
5 Oct · 19:20 → 6 Oct · 05:20 (10.0h)
Moon below horizon during darkness
7.3h total.
Longest window for your filters
5 Oct · 19:20 → 6 Oct · 02:40 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
6 Oct · Mauna Kea
Waning crescent · 11% lit at local midnight.
Astronomical darkness
6 Oct · 19:20 → 7 Oct · 05:20 (10.0h)
Moon below horizon during darkness
8.3h total.
Longest window for your filters
6 Oct · 19:20 → 7 Oct · 03:40 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
7 Oct · Mauna Kea
Waning crescent · 5% lit at local midnight.
Astronomical darkness
7 Oct · 19:20 → 8 Oct · 05:20 (10.0h)
Moon below horizon during darkness
9.3h total.
Longest window for your filters
7 Oct · 19:20 → 8 Oct · 04:40 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
8 Oct · Mauna Kea
Waning crescent · 1% lit at local midnight.
Astronomical darkness
8 Oct · 19:20 → 9 Oct · 05:20 (10.0h)
Moon below horizon during darkness
10.0h total.
Longest window for your filters
8 Oct · 19:20 → 9 Oct · 05:20 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
9 Oct · Mauna Kea
New moon · 0% lit at local midnight.
Astronomical darkness
9 Oct · 19:20 → 10 Oct · 05:20 (10.0h)
Moon below horizon during darkness
10.0h total.
Longest window for your filters
9 Oct · 19:20 → 10 Oct · 05:20 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
10 Oct · Mauna Kea
New moon · 1% lit at local midnight.
Astronomical darkness
10 Oct · 19:20 → 11 Oct · 05:20 (10.0h)
Moon below horizon during darkness
10.0h total.
Longest window for your filters
10 Oct · 19:20 → 11 Oct · 05:20 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
11 Oct · Mauna Kea
Waxing crescent · 4% lit at local midnight.
Astronomical darkness
11 Oct · 19:20 → 12 Oct · 05:20 (10.0h)
Moon below horizon during darkness
10.0h total.
Longest window for your filters
11 Oct · 19:20 → 12 Oct · 05:20 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
12 Oct · Mauna Kea
Waxing crescent · 9% lit at local midnight.
Astronomical darkness
12 Oct · 19:20 → 13 Oct · 05:20 (10.0h)
Moon below horizon during darkness
9.7h total.
Longest window for your filters
12 Oct · 19:40 → 13 Oct · 05:20 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
13 Oct · Mauna Kea
Waxing crescent · 15% lit at local midnight.
Astronomical darkness
13 Oct · 19:20 → 14 Oct · 05:20 (10.0h)
Moon below horizon during darkness
9.0h total.
Longest window for your filters
13 Oct · 20:20 → 14 Oct · 05:20 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
14 Oct · Mauna Kea
Waxing crescent · 22% lit at local midnight.
Astronomical darkness
14 Oct · 19:20 → 15 Oct · 05:20 (10.0h)
Moon below horizon during darkness
8.0h total.
Longest window for your filters
14 Oct · 21:20 → 15 Oct · 05:20 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
15 Oct · Mauna Kea
Waxing crescent · 30% lit at local midnight.
Astronomical darkness
15 Oct · 19:20 → 16 Oct · 05:20 (10.0h)
Moon below horizon during darkness
7.3h total.
Longest window for your filters
15 Oct · 22:00 → 16 Oct · 05:20 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
16 Oct · Mauna Kea
Waxing crescent · 39% lit at local midnight.
Astronomical darkness
16 Oct · 19:20 → 17 Oct · 05:20 (10.0h)
Moon below horizon during darkness
6.3h total.
Longest window for your filters
16 Oct · 23:00 → 17 Oct · 05:20 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
17 Oct · Mauna Kea
First quarter · 48% lit at local midnight.
Astronomical darkness
17 Oct · 19:20 → 18 Oct · 05:20 (10.0h)
Moon below horizon during darkness
5.7h total.
Longest window for your filters
17 Oct · 23:40 → 18 Oct · 05:20 Meets your minimum duration.
Times in Pacific/Honolulu · approximately 20-minute samples. Geometry only, not a weather forecast.
2 nights in a row meeting 4 h with the moon below the horizon. 18 qualify across the 30.
The usable moonless stretch collapses to nothing around it. A good week for planets, doubles and lunar detail.
The moon moves about 12° east a day, so the dark window shifts roughly fifty minutes later each night. A Friday plan is not a Saturday plan.
Plan somewhere else
Sky geometry only — no weather claims beyond the seven-night forecast. How to plan around the moon →