No naked-eye object in the crosshair
Drag the sky or align heading to the Moon, Sun, or a bright star.
Look 0° az · 25° alt
Desktop planetarium. Drag the sky to look around. Device compass is not in use.
Mercury 91
8,920 naked-eye stars · offline catalog
This page wins on identify plus calibrate, not catalog depth or constellation tourism.
HTTPS plus this tap is required on iOS Safari. Desktop can ignore this and drag.
Reference meridian (Royal Observatory Greenwich). Search your city or use GPS for your local sky.
Observer
Greenwich, United Kingdom
51.4769°, -0.0005°
Auto-filled from city search or GPS. Override to display times in any IANA zone.
Align puts a visible body in the crosshair. On a phone with compass, Align stores a heading offset. The slider nudges that offset. The offset is saved on this device.
No Moon, Sun, or bright named star is above the horizon for this observer time.
This page wins on identify plus calibrate, not catalog depth or constellation tourism.
Browser DeviceOrientation is a best-effort heading. Outdoors it is often 5 to 15 degrees off. Indoors, near steel, or after a MagSafe case it can be worse. This page never claims perfect or arcsecond pointing.
On iOS Safari, motion permission runs only after you tap Enable device compass. AbsoluteOrientationSensor is often missing and is not the primary heading path.
Align to the Moon, Sun, or a bright star you can actually see, or drag the heading offset. The offset stays on this device.
Mercury 91 Night Sky Navigation Phase A is this web tool. Native ARKit and ARCore camera overlays are Phase C and are not shipping in an App Store build from this PR.