The phone is not a telescope. You don't point it at the sky or hold it up to anything. The piece starts as soon as you grant location access.
You can put the phone in your pocket. The listening happens in your ears.
Hold the phone as you listen, or pocket it and simply listen — the music plays either way. Keeping it in hand adds to the spatial design, as the Headphones section explains.
Find a comfortable place. Sit, stand, or walk. The chord is steady enough that you can move around without losing it.
Any headphones work. The chord, the tuning, and the sky's slow rotation come through on whatever you have.
What unlocks the full spatial design is head-tracked spatial audio, available on AirPods Pro, AirPods Max, and AirPods 4 with Active Noise Cancellation. With those, the cosmos stays anchored to the world as you turn your head. A star you hear behind you stays behind you when you look the other way, the same way a real star would.
Wired earbuds and other wireless headphones still give you the spatial chord, but it moves with your head instead of staying anchored.
The spatial design comes alive when you move. Hold the phone while you listen, and as you turn to face a new direction the cosmos stays anchored to the world around you. A star you hear off to one side stays there as you turn, the same way a real star would.
This follows the phone, so when you set it down or lock the screen the spatial scene simply holds still until you pick it up again. It tracks the phone rather than your head — Android has no way to read headphone motion the way iOS does.
The spatial chord is placed around you by per-ear cues, and it moves with your head as you turn. The anchored version, where the cosmos stays fixed to the world as you move, is in the iOS and Android apps.
Speakers in a room work too. The chord and tuning are intact. The spatial design flattens, since the per-ear cues that place a star above or behind you depend on each ear hearing something slightly different.
The cosmos has to be oriented somehow. By default, whichever direction you happen to be facing when the piece starts becomes the front of the piece. The chord is correct, but you don't know which star is which without checking the actual sky.
To line the piece up with true compass directions, so a star to your east in the audio is actually east in the sky, use the compass button.
compass appears once the piece is playing. Tap it, hold the phone still for a few seconds while it samples your heading, and the cosmos rotates to align with true north.
calibrate is the same button, renamed after you've used it once. Tap it any time things feel off, after you've moved a lot or turned around without your headphones, and it re-runs the alignment.
You don't have to use either. They're there if you want to know where you're listening from.
The piece moves slowly. Sit with it for at least ten minutes. The chord changes as the Earth turns, but a single star moves too gradually to notice over the course of a minute. Over an hour, you'll hear that the western voices are gone and the eastern ones have come up.
Daytime is mostly silence. The Sun overwhelms the visible sky and the piece honors that. The Moon and the brightest planets stay audible during the day if they are far enough from the Sun.
Twilight is the most active window. As the sun drops below the horizon, the stars rise gradually through civil twilight, only reaching their full strength when the sky is genuinely dark. The same fade plays in reverse at dawn.
For more on what the piece is and what to listen for, see the about page.
Lock the phone, put it in your pocket, take a walk. The audio keeps playing. Lock-screen play and pause work, and so do the play and pause controls on your headphones.
If another app interrupts (a phone call, a video, a notification with sound), the piece pauses for the interruption and resumes after.