See the sunlight before you go
When does the Milky Way core clear the mountains?
On the new-moon night of 6 May 2027 at Teide National Park, the centre of the Milky Way is in a dark sky from 00:00 over a flat horizon, but from the Roques de García viewpoint it clears the ridge at 01:12 and stays in view until 05:52: 4 h 41 min instead of 5 h 53 min.
See the core clear the ridge at Teide →
New-moon nights in 2027, against the real skyline
Each row is a new-moon night in the core season, at one public viewpoint, in local time. Full darkness means the sun is at least 18° below the horizon. "Clears the ridge" is the first moment in full darkness that the centre of the galaxy stands above the computed skyline in its direction. "In view until" is when it drops behind terrain or dawn begins, whichever comes first.
| Place | Night of | Dark and up, flat horizon | Clears the ridge | In view until | Time in view | Highest |
|---|---|---|---|---|---|---|
| Teide National Park | 7 April | 01:54 | 03:06 | 06:26 | 3 h 20 min (flat 4 h 33 min) | 06:17 · 32° S |
| Teide National Park | 6 May | 00:00 | 01:12 | 05:52 | 4 h 41 min (flat 5 h 53 min) | 04:54 · 33° S |
| Teide National Park | 4 June | 22:35 | 23:18 | 05:33 | 6 h 15 min (flat 6 h 58 min) | 03:00 · 33° S |
| Teide National Park | 4 July | 22:43 | 22:43 | 05:26 | 6 h 43 min (flat 6 h 55 min) | 00:57 · 33° S |
| Teide National Park | 2 August | 22:25 | 22:25 | 03:32 | 5 h 6 min (flat 5 h 34 min) | 23:06 · 33° S |
| Tre Cime di Lavaredo | 7 April | 02:11 | 02:02 | 04:46 | 2 h 44 min (flat 2 h 35 min) | 04:37 · 13° SSE |
| Tre Cime di Lavaredo | 6 May | 00:17 | 00:08 | 03:34 | 3 h 27 min (flat 3 h 17 min) | 03:26 · 14° S |
| Tre Cime di Lavaredo | 4 June | 23:48 | 23:48 | 02:29 | 2 h 42 min (flat 2 h 42 min) | 01:58 · 14° S |
| Tre Cime di Lavaredo | 4 July | 00:00 | 00:00 | 02:30 | 2 h 30 min (flat 2 h 30 min) | 00:07 · 14° S |
| Tre Cime di Lavaredo | 2 August | 22:58 | 22:58 | 01:48 | 2 h 50 min (flat 2 h 54 min) | 23:01 · 14° S |
| Glacier Point, Yosemite | 6 April | 01:20 | 01:39 | 05:01 | 3 h 22 min (flat 3 h 41 min) | 04:55 · 22° S |
| Glacier Point, Yosemite | 6 May | 23:22 | 23:41 | 04:11 | 4 h 30 min (flat 4 h 49 min) | 03:43 · 23° S |
| Glacier Point, Yosemite | 4 June | 22:13 | 22:13 | 03:40 | 5 h 27 min (flat 5 h 27 min) | 01:46 · 23° S |
| Glacier Point, Yosemite | 3 July | 22:21 | 22:21 | 02:56 | 4 h 35 min (flat 5 h 23 min) | 23:53 · 23° S |
| Glacier Point, Yosemite | 2 August | 21:51 | 21:51 | 00:58 | 3 h 7 min (flat 4 h 27 min) | 21:55 · 23° S |
What the ridge changes
- Teide National Park (Roques de García viewpoint, Tenerife): the caldera rim holds the core back by up to 1 h 12 min in spring, and by almost nothing by July, when the core is already up as darkness falls.
- Tre Cime di Lavaredo (Rifugio Auronzo, Dolomites): from the hut, about 2,300 m up, the skyline in the core's rising direction sits slightly below a flat horizon, so the core appears up to 9 min earlier than a flat-horizon calculation says.
- Glacier Point, Yosemite (on the rim near the Glacier Point overlook): the skyline delays the start by up to 19 min in spring, but the bigger loss is in summer, when the ridges to the south-west end the night up to 1 h 21 min early as the core sets behind them.
The overlook itself sits on a cliff edge that the 110 m elevation grid reads as part of the wall below. This pin is about 250 m back on the rim, where the grid agrees with the ground.
Heliora treats the core as visible once it clears the ridge, but counts a night as worthwhile only when the core also reaches 10° above a true horizon in full darkness: below that, the air itself dims it, mountain or not.
Check your own spot
Open Heliora, place the pin where you will stand, choose the date, then open Events and pick Milky Way. Once the terrain has loaded, the card shows when the core clears the terrain at that pin, how long it stays clear, and its highest point. Until then the card says its times are a flat-horizon estimate. Move the pin and it recomputes.
How these numbers are computed, and where they can be wrong: Method and accuracy.