Live Moon Screensaver
The Live Moon screensaver shows the Moon as it looks right now — the real phase and libration imaged by NASA's visualization studio and refreshed hour by hour. It's free, key-less, runs in your browser, and ESC exits.
How the Live Moon screensaver works
The saver loads NASA's hourly Dial-a-Moon visualisation — a rendering of the Moon's exact phase and libration for the current hour, built from Lunar Reconnaissance Orbiter data.
It works out the current hour of the year and fetches that frame, so the Moon you see matches the real sky tonight.
If the image can't load, it falls back to drawing the Moon itself — the lit fraction computed from the lunar cycle on your device.
The phase name and percent illuminated are shown, and it refreshes every hour as the Moon waxes or wanes.
A worked example
Tonight it might read Waxing Gibbous · 78% illuminated, the terminator falling exactly where it does in the real sky, the slight nod of libration matching this hour. Each hour the image updates as the Moon moves through its phase.
Settings & tips
- Show phase info toggles the phase name and illumination overlay.
- Background sets the space color behind the Moon.
- It refreshes hourly, so the phase always matches the current sky.
Frequently asked questions
- Is this the Moon's real phase?
- Yes. It uses NASA's hourly Dial-a-Moon for the current hour, so the phase and libration match the real Moon right now.
- Does it need a key?
- No. NASA's imagery is public and key-less. If the image can't load, it draws the phase itself, so it works offline too.
- What is libration?
- Libration is the Moon's slight rocking that lets us see a bit around its edges over time. The NASA imagery shows it accurately.
- How is this different from Phase of the Moon?
- That one is a stylised render; Live Moon uses NASA's actual hourly imagery of the real Moon.
- Is it free?
- Yes — free, no download, in your browser.