The Moon's phase, illumination, distance, rise and set, the next new and full moons, quarters and eclipses, and its position in the sky, updated every second, with charts of its path through the day, a calendar of its phases, and a picture of the Moon drawn as it looks at that moment from your location, among the stars it's passing. A Windows version of the Moon Info web page.
Get MoonInfo-2.4-win64.zip from the Releases page and unzip it anywhere:
MoonInfo.exe the program (no installation; no DLLs needed)
data\ NASA's Moon maps and the stars (keep this folder beside MoonInfo.exe)
Windows 10 or 11, 64-bit. On Linux or macOS it runs under Wine (which has no Windows location service, so it finds the location from your internet address).
- Date and time: with Automatic checked, the computer's clock: every
value is recalculated each second. Unchecked, type a local date and time,
YYYY-MM-DD HH:MM:SS. - Time of day, < Day, Day >, Play day, Play month: drag the slider to another time on the day shown, step a day back or forward, or run the time forward (a day in about six seconds, a month in about thirty) and watch the Moon move, turn and change phase. The same button stops it; Play speed makes it up to four times slower or faster. Check Automatic to return to now.
- Location: on the first run MoonInfo finds your location, and Use My Location finds it again. It asks Windows' location service first (if it's turned on for desktop apps in Settings > Privacy > Location), then, if that's off or doesn't answer, looks up the approximate location of your internet address at ipinfo.io. Or type the latitude and longitude (degrees, north and east positive) and the elevation.
- Phase name: New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Third Quarter or Waning Crescent (the four principal phases within about half a day of the exact time).
- Distance: from the Earth's center to the Moon's.
- Age: days since the last new moon. Libration: how far the Moon is turned, east-west and north-south, from facing us squarely. Perigee and apogee: when the Moon is next nearest and farthest. A full moon closer than 367,600 km (228,400 miles) is marked as a supermoon.
- Eclipses: the next lunar eclipse (the time of its peak, its kind, and whether the Moon is above your horizon then), and the next solar eclipse visible from your location, with how much of the Sun is covered.
- Charts: at the bottom of the data column, the Moon's path through the day (midnight to midnight): its altitude by the hour, and its altitude by direction (east at the left, through south, west and north). The shaded part is below the horizon, and the dot is the Moon now. The small circles mark that day's moonrise (up arrow) and moonset (down arrow), with their times. (The Moonrise and Moonset rows show the next ones from now, which may be tomorrow's.) The dashed line is the Sun, and the sky in the first chart is colored by the daylight: day, twilight and night. The round chart is the sky looking up: the horizon around the edge (north at the top, east at the left), straight up in the middle.
- Calendar: a little Moon for each day of the month, ringed on the days of the new moon, quarters and full moon. Click a day to show it; the arrows show the months before and after.
- Picture: drawn from NASA's Lunar Reconnaissance Orbiter maps (the LROC color mosaic and LOLA elevations) for the date, time and place: the exact phase, lit from the Sun's direction, with the relief shaded near the terminator; the Moon's libration (the slight wobble that turns different edge features toward us) and its tilt; its apparent size, which changes with its distance; and earthshine faintly lighting the dark side. It's exact for any date, past or future.
- View > Moon as seen from my location turns the picture by the Moon's parallactic angle (the angle between celestial north and straight up at the Moon), so it's tilted as it appears in your sky, roughly upside down in the southern hemisphere. Unchecked, it's shown north up.
- View > Names of the seas and craters labels the picture (more names as it gets bigger).
- View > Stars behind the Moon: the stars the Moon is passing, where they really are, to about magnitude 12 (far more than its glare lets you see). The picture is only a little wider than the Moon, so there are usually just a few; with Play day you can watch them disappear behind it.
- View > Miles and feet: the distance in miles and the elevation in feet (unchecked: km and meters).
- View > Dark mode: light text on a dark window, with a dark title bar. On the first run it follows Windows' app theme.
- The picture grows and shrinks with the window; as you resize it, the window keeps the picture filling its right side. If the window is too short for all the data, scroll it with the scroll bar or the mouse wheel.
Times are in the computer's time zone. Settings are kept in
%APPDATA%\MoonInfo\settings.ini.
Visual Studio 2019 (x64) and CMake:
cmake -S . -B build -G "Visual Studio 16 2019" -A x64
cmake --build build --config Release
Plain Win32, with the Windows 10 SDK 10.0.19041 (for C++/WinRT's
Windows.Devices.Geolocation); no other libraries. NASA's maps aren't in
this repository: copy the data folder from the release zip into the
project folder, and the build copies it beside MoonInfo.exe. (The maps were
made from the CGI Moon Kit's lroc_color_16bit_srgb_4k.tif, as an 8-bit
JPEG, and ldem_16_uint.tif, resampled to 4096 x 2048 as a 16-bit PNG.)
build/Release/mooninfo-test.exe prints the calculations for a time and
place (mooninfo-test <unix seconds> <latitude> <longitude>), or tests
finding the location (mooninfo-test location), or draws the Moon to a BMP
file (mooninfo-test render <unix seconds> <out.bmp> <size>).
MoonInfo is free, open-source software provided as is: no support, no warranty. You're welcome to fork it and change it.
To get in touch (questions, ideas, or just to say hello), post in Discussions.
MoonInfo: MIT license, (c) 2026 Steve Ferrell (LICENSE).
- Calculations: Astronomy Engine, (c) 2019-2023 Don Cross (MIT license).
- Stars: the Tycho-2 catalogue
(Hog et al. 2000), from ESA's Hipparcos mission, by way of VizieR (CDS,
Strasbourg);
tools/make_stars.pymakesdata/moon_stars.binfrom it. - Moon maps: NASA's Scientific Visualization Studio (CGI Moon Kit), from the Lunar Reconnaissance Orbiter's camera (LROC) and laser altimeter (LOLA) teams.
See THIRD-PARTY-NOTICES.txt for details.