MoonExplorer Support

Questions, bug reports and ideas are all welcome.

Email me at

I usually reply within a few days. If you're reporting a problem, please include your device model, its iOS version, and what you were doing when it happened. A screenshot helps too.

Common questions

Why can't I turn on Topocentric orientation?

The setting needs your location. The line under the switch tells you why it's unavailable:

"Location access is turned off for MoonExplorer." Open Settings, go to Privacy & Security › Location Services › MoonExplorer, and choose While Using the App.
"Location services are turned off on this device." Open Settings, go to Privacy & Security › Location Services, and turn Location Services on.

The switch becomes available as soon as you return to the app.

What does Topocentric orientation do?

Normally the reset button returns the globe to a standard view with north at the top. With Topocentric orientation on, the reset button instead turns the Moon to match how it looks from where you are right now. That view includes the Moon's slow wobble (libration) and the angle it sits at in your sky. North may not point up, which is why the N disappears from the reset button.

Does the app work without an internet connection?

Yes. A full view of the Moon is built into the app, so the globe always appears. Sharper imagery and the elevation map are downloaded from NASA as you need them, so those require a connection.

Why is the imagery blurry when I zoom in?

Sharper imagery is downloading. It appears once it arrives, which can take a moment on a slow connection.

What does the scale bar show?

The real distance on the Moon's surface at the centre of the globe, for the current zoom. Towards the edge of the globe the surface curves away from you, so features there look squeezed and the scale bar doesn't apply.

Where does the imagery come from?

The visible-light mosaic is from the Lunar Reconnaissance Orbiter Camera (NASA / LRO / LROC Team / Arizona State University / JPL). The elevation map is from the Lunar Orbiter Laser Altimeter (NASA / LRO / LOLA Team / GSFC / JPL). Both are served by NASA Moon Trek.

Does MoonExplorer collect my data?

No. See the privacy policy for exactly how the app handles your location.