CALCULATED SKY · MOON

Stand on the Moon. Find your Earth.

Choose a lunar landing region, pole or far-side observer. Earth's direction follows lunar rotation and libration, rather than an Earth-day animation.

Launch Observatory ↗Choose another horizon

Calculated planetarium · Astronomy Engine · UTC input / TT ephemerides · HYG J2000 stars

LabelsCelestial gridConstellation figuresStars during daylight

UTC Time speedLIVE UTC

N · 0° E · 90° S · 180° W · 270°

Drag to look around; scroll to zoom. Azimuth 0.0° · altitude 20.0° · field of view 100.0°. The grid is local altitude/azimuth.

OBSERVING DETAILS

Choose an object

What this view represents

A fixed lunar observer, transformed with the IAU lunar pole and prime meridian model, including rotation and libration. Earth stays near the same region for near-side observers and can remain below the far-side horizon.

Lunar surface texture is an illustrative foreground, not a surveyed local terrain model. No atmosphere or refraction is applied. The sphere-based horizon and IAU orientation are approximations; lunar ephemeris RA/Dec values are J2000 observer-relative directions.

Sun, Moon and Earth disks use calculated angular diameters; distant planets and satellites may use illustrative markers. A geometric view does not guarantee optical visibility.

Reference frames and lunar sky ↗Astronomy Engine source ↗Data and license registry ↗

Observe with context

Object directions and disk sizes are calculated; overlays and foregrounds help illustrate them. Saved views keep your location, time, camera and settings. Video capture follows the selected UTC speed and uses the same recording and entitlement infrastructure as the simulator.

Frames, approximations and sources ↗

Stand on the Moon. Find your Earth.

Moon Sky Observatory

Observe with context